Substituted 2-phenylpyridines

ABSTRACT

2-Phenylpyridines I ##STR1## wherein X is a chemical bond, 1,2-ethynediyl or optionally substituted --(CH 2 ) 1-3  --, --O--(CH 2 ) 1-2  --, --s--(CH 2 ) 1-2  --, --CH 2  --O--CH 2  --, --CH 2  --S--CH 2  -- or --CH═CH--; 
     Y is oxygen or sulfur; 
     Z 1  is oxygen, sulfur or --N(R 7 )--; 
     Z 2  is oxygen, sulfur or --N(R 8 )--; 
     R 1 , R 2 , R 7  and R 8  independently of one another are hydrogen, optionally substituted alkyl, alkenyl, alkynyl, cycloalkyl, phenyl or heterocyclyl; or 
     R 1  and R 2  or R 7 , or R 2  and R 8  together are optionally substituted --(CH 2 ) 2-5  -- or --(CH 2 ) 2  --O--(CH 2 ) 2  --, or 
     R 1  and R 2  together are optionally substituted 1,2-phenylene; 
     R 3  is cyano, halogen, alkyl, haloalkyl, alkoxy or haloalkoxy; 
     R 4  and R 5  are hydrogen or halogen; 
     R 6  is halogen or haloalkyl; 
     n is zero or one; 
     and their salts are suitable for controlling undesirable vegetation and as desiccants or defoliants.

This application is a 371 of PCT/EP97/00735 filed Feb. 17, 1997, now WO97/30059 Aug. 21, 1997.

The present invention relates to novel substituted 2-phenylpyridines ofthe formula I ##STR2## where the variables have the following meanings:

X is a chemical bond, 1,2-ethynediyl or

a methylene, 1,2-ethanediyl or 1,3-propylene bridge, which, if desired,can have attached to it a hydroxyl, amino or C₁ -C₄ -alkylaminosubstituent;

methyleneoxymethylene, methylenethiamethylene, ethene-1,2-diyl or

oxymethylene, thiamethylene, oxyethylene or thiaethylene, bonded to thephenyl ring via the hetero atom, it being possible, if desired, for thelast two chains to have a hydroxyl, amino or C₁ -C₄ -alkylamino groupattached to the carbon atom adjacent to the phosphorous;

and it being possible for each of the last-mentioned 10 bridges to haveattached to it one or two of the following substituents: cyano,carboxyl, halogen, C₁ -C₄ -alkyl, C₁ -C₄ -haloalkyl, C₁ -C₄ -alkoxy, C₁-C₄ -haloalkoxy, (C₁ -C₄ -alkoxy)carbonyl and/or di-(C₁ -C₄-alkyl)amino;

Y is oxygen or sulfur;

Z¹ is oxygen, sulfur or --N(R⁷)--;

Z² is oxygen, sulfur or --N(R⁸)--;

R¹, R², R⁷ and R⁸ independently of one another are hydrogen, C₁ -C₆-alkyl, C₁ -C₆ -haloalkyl, hydroxy-C₁ -C₄ -alkyl, cyano-C₁ -C₄ -alkyl,C₁ -C₄ -alkoxy-C₁ -C₄ -alkyl, C₁ -C₄ -haloalkoxy-C₁ -C₄ -alkyl, C₃ -C₄-alkenyloxy-C₁ -C₄ -alkyl, C₃ -C₄ -alkynyloxy-C₁ -C₄ -alkyl, C₃ -C₈-cycloalkoxy-C₁ -C₄ -alkyl, amino-C₁ -C₄ -alkyl, C₁ -C₄ -alkylamino-C₁-C₄ alkyl, di(C₁ -C₄ -alkyl)amino-C₁ -C₄ -alkyl, C₁ -C₄ -alkylthio-C₁-C₄ -alkyl, C₁ -C₄ -haloalkylthio-C₁ -C₄ -alkyl, C₃ -C₄ -alkenylthio-C₁-C₄ -alkyl, C₃ -C₄ -alkynylthio-C₁ -C₄ -alkyl, C₁ -C₄ -alkylsulfinyl-C₁-C₄ -alkyl, C₁ -C₄ -haloalkylsulfinyl-C₁ -C₄ -alkyl, C₃ -C₃-alkenylsulfinyl-C₁ -C₄ -alkyl, C₃ -C₄ -alkynylsulfinyl-C₁ -C₄ -alkyl,C₁ -C₄ -alkylsulfonyl-C₁ -C₄ -alkyl, C₁ -C₄ -haloalkylsulfonyl-C₁ -C₄-alkyl, C₃ -C₄ -alkenylsulfonyl-C₁ -C₄ -alkyl, C₃ -C₄-alkynylsulfonyl-C₁ -C₄ -alkyl, C₃ -C₆ -alkenyl, C₃ -C₆ -haloalkenyl,cyano-C₃ -C₆ -alkenyl, C₃ -C₆ -alkynyl, C₃ -C₆ -haloalkynyl, cyano-C₃-C₆ -alkynyl, hydroxycarbonyl-C₁ -C₄ -alkyl, (C₁ -C₄ -alkoxy)carbonyl-C₁-C₄ -alkyl, (C₁ -C₄ -alkylthio)carbonyl-C₁ -C₄ -alkyl, aminocarbonyl-C₁-C₄ -alkyl, (C₁ -C₄ -alkyl)aminocarbonyl-C₁ -C₄ -alkyl, di(C₁ -C₄-alkyl)aminocarbonyl-C₁ -C₄ -alkyl, C₃ -C₈ -cycloalkyl, C₃ -C₈-cycloalkyl-C₁ -C₄ -alkyl, phenyl, phenyl-C₁ -C₄ -alkyl or 3- to7-membered heterocyclyl or heterocyclyl-C₁ -C₄ -alkyl, it beingpossible, if desired, for all heterocycles to contain a carbonyl orthiocarbonyl ring member, and it being possible for all cycloalkyl,phenyl and heterocyclyl rings to be unsubstituted or to have attached tothem one to four substituents, in each case selected from the groupconsisting of halogen, cyano, nitro, amino, hydroxyl, carboxyl, C₁ -C₄-alkyl, C₁ -C₄ -haloalkyl, C₁ -C₄ -alkoxy, C₁ -C₄ -haloalkoxy, C₁ -C₄-alkylthio, C₁ -C₄ -haloalkylthio, C₁ -C₄ -alkylsulfonyl, C₁ -C₄-haloalkylsulfonyl, (C₁ -C₄ -alkyl)carbonyl, (C₁ -C₄-haloalkyl)carbonyl, (C₁ -C₄ -alkoxy)carbonyl, (C₁ -C₄-alkyl)carbonyloxy, (C₁ -C₄ -haloalkyl)carbonyloxy and di(C₁ -C₄-alkyl)amino, or

R¹ and R² or R¹ and R⁷ and/or R² and R⁸ in each case together form a1,2-ethanediyl, 1,3-propylene, tetramethylene, pentamethylene orethyleneoxyethylene chain which, if desired, can be substituted by oneto four C₁ -C₄ -alkyl and/or one or two (C₁ -C₄ -alkoxy)carbonyl groups,or

R¹ and R² together are 1,2-phenylene which can be unsubstituted or haveattached to it one to three substituents, in each case selected from thegroup consisting of cyano, nitro, halogen, C₁ -C₄ -alkyl, C₁ -C₄-haloalkyl, C₁ -C₄ -alkoxy and C₁ -C₄ -haloalkoxy;

R³ is cyano, halogen, C₁ -C₄ -alkyl, C₁ -C₄ -haloalkyl, C₁ -C₄ -alkoxyor C₁ -C₄ -haloalkoxy;

R⁴, R⁵ in each case are hydrogen or halogen;

R⁶ is halogen or C₁ -C₄ -haloalkyl;

n is zero or one;

and to the agriculturally useful salts of the compounds I.

Furthermore, the invention relates to

the use of the compounds I as herbicides or for thedesiccation/defoliation of plants,

herbicidal compositions and compositions for the desiccation/defoliationof plants which comprise the compounds I as active substances,

processes for the preparation of the compounds I and of herbicidalcompositions and compositions for the desiccation/defoliation of plantswhich make use of the compounds I, and

methods of controlling undesirable vegetation and for thedesiccation/defoliation of plants using the compounds I.

U.S. Pat. No. 5,434,288 describes certain benzene derivatives asphospholipase A2 inhibitors. The broad definition of these compoundsalso includes some of the present substituted 2-phenylpyridines I if thesuitable substituents are selected.

Furthermore, some of the compounds I--when suitable substituents arechosen--come under the general formulae of

platelet-activating factor (PAF) antagonists described in GB-A 2 263109;

supported catalysts for the production of acetic acid which aredescribed in DE-A 41 21 959;

antithrombic, antiaggregatory and tumor-inhibitor reactive substancesdescribed in EP-A 537 696;

intermediates for the preparation of certain NMDA receptor inhibitors,mentioned in EP-A 421 436;

intermediates for the preparation of certain insecticides, mentioned inEP-A 544 587;

intermediates for the preparation of certain PDE IV inhibitors,mentioned in WO 95/35281;

intermediates for the preparation of asymmetric9-cyanostyryl-10-styrylanthracene derivatives, mentioned in JP-A 05/178810;

intermediates for the preparation of certain insecticides, acaricides,nematicides and fungicides, mentioned in EP-A 474 042.

2-Phenylpyridines as herbicides or for the desiccation/defoliation ofplants have already been taught in WO 95/02580.

However, the herbicidal properties of the prior-art 2-phenylpyridineswith regard to the harmful plants are not always entirely satisfactory.

It is an object of the present invention to provide novel herbicidallyactive 2-phenylpyridines which allow better targeted control ofundesirable plants than has been possible to date. The object alsoextends to the provision of novel compounds which act asdesiccants/defoliants.

We have found that this object is achieved by the present substituted2-phenylpyridines of the formula I and by their herbicidal activity.

Furthermore, there have been found herbicidal compositions whichcomprise the compounds I and which have a very good herbicidal activity.Moreover, there have been found processes for the preparation of thesecompositions and methods of controlling undesirable vegetation using thecompounds I.

In addition, we have found that the compounds I are also suitable forthe desiccation/defoliation of parts of plants, suitable plants beingcrop plants such as cotton, potatoes, oilseed rape, sunflowers, soybeansor field beans, in particular cotton. Thus, we have found compositionsfor the desiccation and/or defoliation of plants, processes for thepreparation of these compositions and methods for the desiccation and/ordefoliation of plants using the compounds I.

Depending on the substitution pattern, the compounds of the formula Ican contain one or more chiral centers, in which case they are presentin the form of enantiomer or diastereomer mixtures. E/Z isomers are alsopossible, depending on the meaning of X. The invention relates both tothe pure enantiomers or diasteromers and to mixtures of these.

Agriculturally useful salts are to be understood mainly as the salts ofI with those cations, and acid addition salts of I with those acids,which do not adversely affect the herbicidal or desiccation/defoliantaction of I.

Thus, suitable cations are, in particular, the ions of the alkalimetals, preferably sodium and potassium, of the alkaline earth metals,preferably calcium, magnesium and barium, and of the transition metals,preferably manganese, copper, zinc and iron, and the ammonium ion, whichcan have attached to it a C₁ -C₄ -alkyl, phenyl or benzyl substituentand, if desired, additionally one to three further C₁ -C₄ -alkylradicals, preferably diisopropylammonium, tetramethylammonium,tetrabutylammonium, trimethylbenzylammonium, furthermore phosphoniumions, preferably tri-(C₁ -C₄ -alkyl)phosphonium, sulfonium ions,preferably tri(C₁ -C₄ -alkyl)sulfonium, and sulfoxonium ions, preferablytri(C₁ -C₄ -alkyl)sulfoxonium.

Anions of useful acid addition salts are mainly fluoride, chloride,bromide, hydrogen sulfate, sulfate, dihydrogen phosphate, hydrogenphosphate, phosphate, nitrate, hydrogen carbonate, carbonate,hexafluorosilicate, hexafluorophosphate, benzoate, oxalate,dodecylbenzenesulfonate, and the anions of C₁ -C₄ -alkanoic acids,preferably formate, acetate, propionate and butyrate.

The organic moieties mentioned for the substituents R¹ to R³ and R⁶ toR⁸ or as radicals on X represent collective terms for individualenumerations of the individual group members. All carbon chains, i.e.all alkyl, haloalkyl, hydroxyalkyl, cyanoalkyl, aminoalkyl,hydroxycarbonylalkyl, aminocarbonylalkyl, alkoxy, haloalkoxy, alkylthio,haloalkylthio, alkylsulfinyl, halosulfinyl, alkylsulfonyl,haloalkylsulfonyl, alkylamino, dialkylamino, alkenyl, haloalkenyl,cyanoalkenyl, alkenyloxy, alkenylthio, alkenylsulfinyl, alkenylsulfonyl,alkynyl, haloalkynyl, cyanoalkynyl, alkynyloxy, alkynylthio,alkynylsulfinyl, alkynylsulfonyl moieties, can be straight-chain orbranched. Halogenated substituents preferably have attached to them oneto five identical or different halogen atoms.

The meaning of halogen is in each case fluorine, bromine, chlorine oriodine, in particular fluorine or chlorine.

Other examples of meanings are:

C₁ -C₄ -alkyl: methyl, ethyl, n-propyl, 1-methylethyl, n-butyl,1-methylpropyl, 2-methylpropyl or 1,1-dimethylethyl, in particularmethyl or ethyl;

C₁ -C₄ -haloalkyl: a C₁ -C₄ -alkyl radical as mentioned above which ispartially or fully substituted by fluorine, chlorine, bromine and/oriodine, i.e., for example, chloromethyl, dichloromethyl,trichloromethyl, fluoromethyl, difluoromethyl, trifluoromethyl,chlorofluoromethyl, dichlorofluoromethyl, chlorodifluoromethyl,2-fluoroethyl, 2-chloroethyl, 2-bromoethyl, 2-iodoethyl,2,2-difluoroethyl, 2,2,2-trifluoroethyl, 2-chloro-2-fluoroethyl,2-chloro-2,2-difluoroethyl, 2,2-dichloro-2-fluoroethyl,2,2,2-trichloroethyl, pentafluoroethyl, 2-fluoropropyl, 3-fluoropropyl,2,2-difluoropropyl, 2,3-difluoropropyl, 2-chloropropyl, 3-chloropropyl,2,3-dichloropropyl, 2-bromopropyl, 3-bromopropyl, 3,3,3-trifluoropropyl,3,3,3-trichloropropyl, 2,2,3,3,3-pentafluoropropyl, heptafluoropropyl,1-(fluoromethyl)-2-fluoroethyl, 1-(chloromethyl)-2-chloroethyl,1-(bromomethyl)-2-bromoethyl, 4-fluorobutyl, 4-chlorobutyl, 4-bromobutylor nonafluorobutyl, in particular chloromethyl, fluoromethyl,difluoromethyl, trifluoromethyl, 2-fluoroethyl, 2-chloroethyl or2,2,2-trifluoroethyl;

C₁ -C₆ -alkyl: C₁ -C₄ -alkyl as mentioned above and also, for example,n-pentyl, 1-methylbutyl, 2-methylbutyl, 3-methylbutyl,2,2-dimethylpropyl, 1-ethylpropyl, n-hexyl, 1,1-dimethylpropyl,1,2-dimethylpropyl, 1-methylpentyl, 1-methylpentyl, 2-methylpentyl,3-methylpentyl, 4-methylpentyl, 1,1-dimethylbutyl, 1,2-dimethylbutyl,1,3-dimethylbutyl, 2,2-dimethylbutyl, 2,3-dimethylbutyl,3,3-dimethylbutyl, 1-ethylbutyl, 2-ethylbutyl, 1,1,2-trimethylpropyl,1,2,2-trimethylpropyl, 1-methyl-1-methylpropyl or1-ethyl-2-methylpropyl, in particular methyl, ethyl, n-propyl,1-methylethyl, n-butyl, 1,1-dimethylethyl, n-pentyl or n-hexyl;

C₁ -C₆ -haloalkyl: a C₁ -C₆ -alkyl radical as mentioned above which ispartially or fully substituted by fluorine, chlorine, bromine and/oriodine, i.e., for example, one of the radicals mentioned under C₁ -C₄-haloalkyl, or 5-fluoro-1-pentyl, 5-chloro-1-pentyl, 5-bromine-1-pentyl,5-iodo-1-pentyl, 5,5,5-trichloro-1-pentyl, undecafluoropentyl,6-fluoro-1-hexyl, 6-chloro-1-hexyl, 6-bromo-1-hexyl, 6-iodo-1-hexyl,6,6,6-trichloro-1-hexyl or dodecafluorohexyl, in particularchloromethyl, fluoromethyl, difluoromethyl, trifluoromethyl,2-fluoroethyl, 2-chloroethyl or 2,2,2-trifluoroethyl;

hydroxy-C₁ -C₄ -alkyl: for example hydroxymethyl, 2-hydroxyeth-1-yl,2-hydroxyprop-1-yl, 3-hydroxyprop-1-yl, 1-hydroxyprop-2-yl,2-hydroxybut-1-yl, 3-hydroxybut-1-yl, 4-hydroxybut-1-yl,1-hydroxybut-2-yl, 1-hydroxybut-3-yl, 2-hydroxybut-3-yl,1-hydroxy-2-methylprop-3-yl, 2-hydroxy-2-methylprop-3-yl, or2-hydroxymethylprop-2-yl, in particular 2-hydroxyethyl;

cyano-C₁ -C₄ -alkyl: cyanomethyl, 1-cyanoeth-1-yl, 2-cyanoeth-1-yl,1-cyanoprop-1-yl, 2-cyanoprop-1-yl, 3-cyanoprop-1-yl, 1-cyanoprop-2-yl,2-cyanoprop-2-yl, 1-cyanobut-1-yl, 2cyanobut-1-yl, 3-cyanobut-1-yl,4-cyanobut-1-yl, 1-cyanobut-2-yl, 2-cyanobut-2-yl, 1-cyanobut-3-yl,2-cyanobut-3-yl, 1-cyano-2-methylprop-3-yl, 2-cyano-2-methylprop-3-yl,3-cyano-2-methylprop-3-yl or 2-cyanomethylprop-2-yl, in particularcyanomethyl or 2-cyanoethyl;

amino-C₁ -C₄ -alkyl: for example aminomethyl, 2-aminoethyl,2-aminoprop-1-yl, 3-aminoprop-1-yl, 2-aminobut-1-yl, 3-aminobut-1-yl,4-aminobut-1-yl, 1-aminobut-2-yl, 3-aminobut-2-yl, 4-aminobut-2-yl,1-(aminomethyl)eth-1-yl, 1-(aminomethyl)-1-(methyl)eth-1-yl or1-(aminomethyl)prop-1-yl, in particular aminomethyl or 2-aminoethyl;

hydroxycarbonyl-C₁ -C₄ -alkyl: hydroxycarbonylmethyl,1-(hydroxycarbonyl)ethyl, 2-(hydroxycarbonyl)ethyl,1-(hydroxycarbonyl)prop-1-yl, 2-(hydroxycarbonyl)prop-1-yl,3-(hydroxycarbonyl)prop-1-yl, 1-(hydroxycarbonyl)but-1-yl,2-(hydroxycarbonyl)but-1-yl, 3-(hydroxycarbonyl)but-1-yl,4-(hydroxycarbonyl)but-1-yl, 1-(hydroxycarbonyl)but-2-yl,2-(hydroxycarbonyl(but-2-yl, 3-(hydroxycarbonyl)but-2-yl,4-(hydroxycarbonyl)but-2-yl, 1-(hydroxycarbonylmethyl)eth-1-yl,1-(hydroxycarbonylmethyl)-1-(methyl)eth-1-yl or1-(hydroxycarbonylmethyl)prop-1-yl, in particular hydroxycarbonylmethylor 2-(hydroxycarbonyl)ethyl;

aminocarbonyl-C₁ -C₄ -alkyl: aminocarbonylmethyl,1-(aminocarbonyl)ethyl, 2-(aminocarbonyl)ethyl,1-(aminocarbonyl)prop-1-yl, 2-(aminocarbonyl)prop-1-yl,3-(aminocarbonyl)prop-1-yl, 1-(aminocarbonyl)but-1-yl,2-(aminocarbonyl)but-1-yl, 3-(aminocarbonyl)but-1-yl,4-(aminocarbonyl)but-1-yl, 1-(aminocarbonyl)but-2-yl,2-(aminocarbonyl)but-2-yl, 3-(aminocarbonyl)but-2-yl,4-(aminocarbonyl)but-2-yl, 1-(aminocarbonyl)eth-1-yl,1-(aminocarbonylmethyl)-1-(methyl)eth-1-yl or1-(aminocarbonylmethyl)prop-1-yl, in particular aminocarbonylmethyl or2-(aminocarbonyl)ethyl;

phenyl-C₁ -C₄ -alkyl: benzyl, 1-phenylethyl, 2-phenylethyl,1-phenylprop-1-yl, 2-phenylprop-1-yl, 3-phenylprop-1-yl,1-phenylbut-1-yl, 2-phenylbut-1-yl, 3-phenylbut-1-yl, 4-phenylbut-1-yl,1-phenylbut-2-yl, 2-phenylbut-2-yl, 3-phenylbut-2-yl, 4-phenylbut-2-yl,1-(phenylmethyl)eth-1-yl, 1-(phenylmethyl)-1-(methyl)eth-1-yl, or1-(phenylmethyl)prop-1-yl, in particular benzyl or 2-phenylethyl;

heterocyclyl-C₁ -C₄ -alkyl: heterocyclylmethyl, 1-heterocyclylethyl,2-heterocyclyethyl, 1-heterocyclylprop-1-yl, 2-heterocyclylprop-1-yl,3-heterocyclylprop-1-yl, 1-heterocyclylbut-1-yl, 2-heterocyclylbut-1-yl,3-heterocyclylbut-1-yl, 4-heterocyclylbut-1-yl, 1-heterocyclylbut-2-yl,2-heterocyclylbut-2-yl, 3-heterocyclylbut-2-yl, 4-heterocyclylbut-2-yl,1-(heterocyclylmethyl)eth-1-yl,1-(heterocyclylmethyl)-1-(methyl)eth-1-yl or1-(heterocyclylmethyl)prop-1-yl, in particular heterocyclylmethyl,2-heterocyclylethyl or 3-heterocyclylpropyl; 3-oxetanylmethyl,2-(1,3-oxazolin-2-on-3yl)ethyl and 3-(2-pyridyl)propyl are especiallypreferred;

(C₁ -C₄ -alkyl)carbonyl: CO--CH₃, CO--C₂ H₅, n-propylcarbonyl,1-methylethylcarbonyl, n-butylcarbonyl, CO--CH(CH₃)₂,2-methylpropylcarbonyl or CO--C(CH₃)₃, in particular CO--CH₃ ;

(C₁ -C₄ -haloalkyl)carbonyl: a (C₁ -C₄ -alkyl)carbonyl radical asmentioned above which is partially or fully substituted by fluorine,chlorine, bromine and/or iodine, i.e., for example, chloroacetyl,dichloroacetyl, trichloroacetyl, fluoroacetyl, difluoroacetyl,trifluoroacetyl, chlorofluoroacetyl, dichlorofluoroacetyl,chlorodifluoroacetyl, 2-fluoroethylcarbonyl, 2-chloroethylcarbonyl,2-bromoethylcarbonyl, 2-iodoethylcarbonyl, 2,2-difluoroethylcarbonyl,2,2,2-trifluoroethylcarbonyl, 2-chloro-2-fluoroethylcarbonyl,2-chloro-2,2-difluoroethylcarbonyl, 2,2-dichloro-2-fluoroethylcarbonyl,2,2,2-trichloroethylcarbonyl, CO--C₂ F₅, 2-fluoropropylcarbonyl,3-fluoropropylcarbonyl, 2,2-difluoropropylcarbonyl,2,3-difluoropropylcarbonyl, 2-chloropropylcarbonyl,3-chloropropylcarbonyl, 2,3-dichloropropylcarbonyl,2-bromopropylcarbonyl, 3-bromopropylcarbonyl,3,3,3-trifluoropropylcarbonyl, 3,3,3-trichloropropylcarbonyl,2,2,3,3,3-pentafluoropropylcarbonyl, heptafluoropropylcarbonyl,1-(fluoromethyl)-2-fluoroethylcarbonyl,1-(chloromethyl)-2-chloroethylcarbonyl,1-(bromomethyl-2-bromoethylcarbonyl, 4-fluorobutylcarbonyl,4-chlorobutylcarbonyl, 4-bromobutylcarbonyl or nonafluorobutylcarbonyl,in particular trifluoroacetyl;

(C₁ -C₄)carbonyloxy: acetyloxy, ethylcarbonyloxy, n-propylcarbonyloxy,1-methylethylcarbonyloxy, n-butylcarbonyloxy, 1-methylpropylcarbonloxy,2-methylpropylcarbonloxy or 1,1-dimethylethylcarbonyloxy, in particularacetyloxy;

(C₁ -C₄ -haloalkyl)carbonyloxy: a (C₁ -C₄ -alkyl)carbonyloxy radical asmentioned above which is partially or fully substituted by fluorine,chlorine, bromine and/or iodine, i.e., for example, chloroacetyloxy,dichloroacetyloxy, trichloroacetyloxy, fluoroacetyloxy,difluoroacetyloxy, trifluoroacetyloxy, chlorofluoroacetyloxy,dichlorofluoroacetyloxy, chlorodifluoroacetyloxy,2-fluoroethylcarbonyloxy, 2-chloroethylcarbonyloxy,2-bromoethylcarbonyloxy, 2-iodoethylcarbonyloxy,2,2-difluoroethylcarbonyloxy, 2,2,2-trifluoroethylcarbonyloxy,2-chloro-2-fluoroethylcarbonyloxy,2-chloro-2,2-difluoroethylcarbonyloxy,2,2-dichloro-2-fluoroethylcarbonyloxy, 2,2,2-trichloroethylcarbonyloxy,pentafluoroethylcarbonyloxy, 2-fluoropropylcarbonyloxy,3-fluoropropylcarbonyloxy, 2,2-difluoropropylcarbonyloxy,2,3-difluoropropylcarbonyloxy, 2-chloropropylcarbonyloxy,3-chloropropylcarbonyloxy, 2,3-dichloropropylcarbonyloxy,2-bromopropylcarbonyloxy, 3-bromopropylcarbonyloxy,3,3,3-trifluoropropylcarbonyloxy, 3,3,3-trichloropropylcarbonyloxy,2,2,3,3,3-pentafluoropropylcarbonyloxy, heptafluoropropylcarbonyloxy,1-(fluoromethyl)-2-fluoroethylcarbonyloxy,1-(chloromethyl)-2-chloroethylcarbonyloxy,1-(bromomethyl)-2-bromoethylcarbonyloxy, 4-fluorobutylcarbonyloxy,4-chlorobutylcarbonyloxy, 4-bromobutyl or nonafluorobutyl, in particulartrifluoroacetoxy;

C₁ -C₄ -alkoxy: methoxy, ethoxy, n-propoxy, 1-methylethoxy, n-butoxy,1-methylpropoxy, 2-methylpropoxy or 1,1-dimethylethoxy, in particularmethoxy or ethoxy;

C₁ -C₄ -haloalkoxy: a C₁ -C₄ -alkoxy radical as mentioned above which ispartially or fully substituted by fluorine, chlorine, bromine and/oriodine, i.e., for example, chloromethoxy, dichloromethoxy,trichloromethoxy, fluoromethoxy, difluoromethoxy, trifluoromethoxy,chlorofluoromethoxy, dichlorofluoromethoxy, chlorodifluoromethoxy,2-fluoroethoxy, 2-chloroethoxy, 2-bromoethoxy, 2-iodoethoxy,2,2-difluoroethoxy, 2,2,2-trifluoroethoxy, 2-chloro-2-fluoroethoxy,2-chloro-2,2-difluoroethoxy, 2,2-dichloro-2-fluoroethoxy,2,2,2-trichloroethoxy, OC₂ F₅, 2-fluoropropoxy, 3-fluoropropoxy,2,2-difluoropropoxy, 2,3-difluoropropoxy, 2-chloropropoxy,3-chloropropoxy, 2,3-dichloropropoxy, 2-bromopropoxy, 3-bromopropoxy,3,3,3-trifluoropropoxy, 3,3,3-trichloropropoxy,2,2,3,3,3-pentafluoropropoxy, heptafluoropropoxy,1-(fluoromethyl)-2-fluoroethoxy, 1-(chloromethyl)-2-chloroethoxy,1-(bromomethyl)-2-bromoethoxy, 4-fluorobutoxy, 4-chlorobutoxy,4-bromobutoxy or nonafluorobutoxy, in particular 2-chloroethoxy or2,2,2-trifluoroethoxy;

(C₁ -C₄ -alkoxy)carbonyl: methoxycarbonyl, ethoxycarbonyl,n-propoxycarbonyl, 1-methylethoxycarbonyl, n-butoxycarbonyl,1-methylpropoxycarbonyl, 2-methylpropoxycarbonyl or1,1-dimethylethoxycarbonyl, in particular methoxycarbonyl orethoxycarbonyl;

C₁ -C₆ -alkylthio: methylthio, ethylthio, n-propylthio,1-methylethylthio, n-butylthio, 1-methylpropylthio, 2-methylpropylthioor 1,1-dimethylethylthio, in particular methylthio or ethylthio;

C₁ -C₄ -alkylamino: methylamino, ethylamino, n-propylamino,1-methylethylamino, n-butylamino, 1-methylpropylamino,2-methylpropylamino or 1,1-dimethylethylamino, in particular methylaminoor ethylamino;

di(C₁ -C₄ -alkyl)amino: N,N-dimethylamino, N,N-diethylamino,N,N-dipropylamino, N,N-di(1-methylethyl)amino, N,N-dibutylamino,N,N-di(1-methylpropyl)amino, N,N-di(2-methylpropyl)amino,N,N-di(1,1-dimethylethyl)amino, N-ethyl-N-methylamino,N-methyl-N-propylamino, N-methyl-N-(1-methylethyl)amino,N-butyl-N-methylamino, N-methyl-N-(1-methylpropyl)amino,N-methyl-N-(2-methylpropyl)amino, N-(1,1-dimethylethyl)-N-methylamino,N-ethyl-N-propylamino, N-ethyl-N-(1-methylethyl)amino,N-butyl-N-ethylamino, N-ethyl-N-(1-methylpropyl)amino,N-ethyl-N-(2-methylpropyl)amino, N-ethyl-N-(1,1-dimethylethyl)amino,N-(1-methylethyl)-N-propylamino, N-butyl-N-propylamino,N-(1-methylpropyl)-N-propylamino, N-(2-methylpropyl)-N-propylamino,N-(1,1-dimethylethyl)-N-propylamino, N-butyl-N-(1-methylethyl)amino,N-(1-methylethyl)-N-(1-methylpropyl)amino,N-(1-methylethyl)-N-(2-methylpropyl)amino,N-(1,1-dimethylethyl)-N-(1-methylethyl)amino,N-butyl-N-(1-methylpropyl)amino, N-butyl-N-(2-methylpropyl)amino,N-butyl-N-(1,1-dimethylethyl)amino,N-(1-methylpropyl)-N-(2-methylpropyl)amino,N-(1,1-dimethyl-ethyl)-N-(1-methylpropyl)amino orN-(1,1-dimethyl-ethyl)-N-(2-methylpropyl)amino, in particular N(CH₃)₂ orN(C₂ H₅)₂ ;

C₁ -C₄ -alkoxy-C₁ -C₄ -alkyl: C₁ -C₄ -alkyl which is substituted by C₁-C₄ -alkoxy as mentioned above, i.e., for example, methoxymethyl,ethoxymethyl, n-propoxymethyl, (1-methylethoxy)methyl, n-butoxymethyl,(1-methylpropoxy)methyl, (2-methylpropoxy)methyl,(1,1-dimethylethoxy)methyl, 2-(methoxy)ethyl, 2-(ethoxy)ethyl,2-(n-propoxy)ethyl, 2-(1-methylethoxy)ethyl, 2-(n-butoxy)ethyl,2-(1-methylpropoxy)ethyl, 2-(2-methylpropoxy)ethyl,2-(1,1-dimethylethoxy)ethyl, 2-(methoxy)propyl, 2-(ethoxy)propyl,2-(n-propoxy)propyl, 2-(1-methylethoxy)propyl, 2-(n-butoxy)propyl,2-(1-methylpropoxy)propyl, 2-(2-methylpropoxy)propyl,2-(1,1-dimethylethoxy)propyl, 3-(methoxy)propyl, 3-(ethoxy)propyl,3-(n-propoxy)propyl, 3-(1-methylethoxy)propyl, 3-(n-butoxy)propyl,3-(1-methylpropoxy)propyl, 3-(2-methylpropoxy)propyl,3-(1,1-dimethylethoxy)propyl, 2-(methoxy)butyl, 2-(ethoxy)butyl,2-(n-propoxy)butyl, 2-(1-methylethoxy)butyl, 2-(n-butoxy)butyl,2-(1-methylpropoxy)butyl, 2-(2-methylpropoxy)butyl,2-(1,1-dimethylethoxy)butyl, 3-(methoxy)butyl, 3-(ethoxy)butyl,3-(n-propoxy)butyl, 3-(1-methylethoxy)butyl, 3-(n-butoxy)butyl,3-(1-methylpropoxy)butyl, 3-(2-methylpropoxy)butyl,3-(1,1-dimethylethoxy)butyl, 4-(methoxy)butyl, 4-(ethoxy)butyl,4-(n-propoxy)butyl, 4-(1-methylethoxy)butyl, 4-(n-butoxy)butyl,4-(1-methylpropoxy)butyl, 4-(2-methylpropoxy)butyl or4-(1,1-dimethylethoxy)butyl, in particular methoxymethyl or2-methoxyethyl;

(C₁ -C₄ -alkoxy)carbonyl-C₁ -C₄ -alkyl: C₁ -C₄ -alkyl which issubstituted by (C₁ -C₄ -alkoxy)carbonyl as mentioned above, i.e., forexample, methoxycarbonylmethyl, ethoxycarbonylmethyl,1-(methoxycarbonyl)ethyl or 2-(methoxycarbonyl)ethyl;

C₁ -C₄ -alkylthio-C₁ -C₄ -alkyl: C₁ -C₄ -alkyl which is substituted byC₁ -C₄ -alkylthio as mentioned above, i.e., for example,methylthiomethyl, ethylthiomethyl, n-propylthiomethyl,(1-methylethylthio)methyl, n-butylthiomethyl,(1-methylpropylthio)methyl, (2-methylpropylthio)methyl,(1,1-dimethylethylthio)methyl, 2-methylthioethyl, 2-ethylthioethyl,2-(n-propylthio)ethyl, 2-(1-methylethylthio)ethyl, 2-(n-butylthio)ethyl,2-(1-methylpropylthio)ethyl, 2-(2-methylpropylthio)ethyl,2-(1,1-dimethylethylthio)ethyl, 2-(methylthio)propyl,3-(methylthio)propyl, 2-(ethylthio)propyl, 3-(ethylthio)propyl,3-(propylthio)propyl, 3-(butylthio)propyl, 4-(methylthio)butyl,4-(ethylthio)butyl, 4-(n-propylthio)butyl, or 4-(n-butylthio)butyl, inparticular 2-(methylthio)ethyl;

(C₁ -C₄ -alkylthio)carbonyl-C₁ -C₄ -alkyl: C₁ -C₄ -alkyl which issubstituted by (C₁ -C₄ -alkylthio)carbonyl such as (methylthio)carbonyl,(ethylthio)carbonyl, (n-propylthio)carbonyl,(1-methylethylthio)carbonyl, (n-butylthio)carbonyl,(1-methylpropylthio)carbonyl, (2-methylpropylthio)carbonyl and(1,1-dimethylethylthio)carbonyl, preferably (methylthio)carbonyl or(ethylthio)carbonyl, i.e., for example, (methylthio)carbonylmethyl,(ethylthio)carbonylmethyl, 1-[(methylthio)carbonyl]ethyl or2-[(methylthio)carbonyl]ethyl;

C₁ -C₄ -haloalkylthio-C₁ -C₄ -alkyl: C₁ -C₄ -alkyl as mentioned abovewhich as attached to it a C₁ -C₄ -alkylthio group which is partially orfully substituted by fluorine, chlorine and/or bromine, e.g.difluoromethylthio, trifluoromethylthio, chlorodifluoromethylthio,bromodifluoromethylthio, 2-fluoroethylthio, 2-chloroethylthio,2-bromoethylthio, 2-iodoethylthio, 2,2-difluoroethylthio,2,2,2-trifluoroethylthio, 2,2,2-trifluoroethylthio,2-chloro-2-fluoroethylthio, 2-chloro-2,2-difluoroethylthio,2,2-dichloro-2-fluoroethylthio, pentafluoroethylthio,2-fluoropropylthio, 3-fluoropropylthio, 2-chloropropylthio,3-chloropropylthio, 2-bromopropylthio, 3-bromopropylthio,2,2-difluoropropylthio, 2,3-difluoropropylthio, 2,3-dichloropropylthio,3,3,3-trifluoropropylthio, 3,3,3-trichloropropylthio,2,2,3,3,3-pentafluoropropylthio, heptafluoropropylthio,1-(fluoromethyl)-2-fluoroethylthio, 1-(chloromethyl)-2-chloroethylthio,1-(bromomethyl)-2-bromoethylthio, 4-fluorobutylthio, 4-chlorobutylthioor 4-bromobutylthio, i.e., for example, difluoromethylthiomethyl;

C₁ -C₄ -alkylamino-C₁ -C₄ -alkyl: C₁ -C₄ -alkyl which is substituted byC₁ -C₄ -alkylamino as mentioned above, i.e., for example,methylaminomethyl, ethylaminomethyl, n-propylaminomethyl,(1-methylethylamino)methyl, n-butylaminomethyl,(1-methylpropylamino)methyl, (2-methylpropylamino)methyl,(1,1-dimethylethylamino)methyl, 2-methylaminoethyl, 2-ethylaminoethyl,2-(n-propylamino)ethyl, 2-(1-methylethylamino)ethyl,2-(n-butylamino)ethyl, 2-(1-methylpropylamino)ethyl,2-(2-methylpropylamino)ethyl, 2-(1,1-dimethylethylamino)ethyl,2-(methylamino)propyl, 3-(methylamino)propyl, 2-(ethylamino)propyl,3-(ethylamino)propyl, 3-(propylamino)propyl, 3-(butylamino)propyl,4-(methylamino)butyl, 4-(ethylamino)butyl, 4-(n-propylamino)butyl or4-(n-butylamino)butyl, in particular 2-(methylamino)ethyl;

C₁ -C₄ -alkylaminocarbonyl-C₁ -C₄ -alkyl: C₁ -C₄ -alkyl which issubstituted by C₁ -C₄ -alkylaminocarbonyl such as methylaminocarbonyl,ethylaminocarbonyl, n-propylaminocarbonyl, 1-methylethylaminocarbonyl,n-butylaminocarbonyl, 1-methylpropylaminocarbonyl,2-methylpropylaminocarbonyl or 1,1-dimethylethylaminocarbonyl,preferably methylaminocarbonyl or ethylaminocarbonyl, i.e., for example,(methylaminocarbonyl)methyl, (ethylaminocarbonyl)methyl,1-(methylaminocarbonyl)ethyl or 2-(methylaminocarbonyl)ethyl;

di(C₁ -C₄ -alkyl)amino-C₁ -C₄ -alkyl: C₁ -C₄ -alkyl which is substitutedby di(C₁ -C₄ -alkyl)amino as mentioned above, i.e., for example,dimethylaminomethyl or diethylaminomethyl;

di(C₁ -C₄ -alkyl)aminocarbonyl-C₁ -C₄ -alkyl: C₁ -C₄ -alkyl which issubstituted by di(C₁ -C₄ -alkyl)aminocarbonyl such asN,N-dimethylaminocarbonyl, N,N-diethylaminocarbonyl,N,N-dipropylaminocarbonyl, N,N-di(1-methylethyl)aminocarbonyl,N,N-dibutylaminocarbonyl, N,N-di(1-methylpropyl)aminocarbonyl,N,N-di(2-methylpropyl)aminocarbonyl,N,N-di(1,1-dimethylethyl)aminocarbonyl, N-ethyl-N-methylaminocarbonyl,N-methyl-N-propylaminocarbonyl, N-methyl-N-(1-methylethyl)aminocarbonyl,N-butyl-N-methylaminocarbonyl, N-methyl-N-(1-methylpropyl)aminocarbonyl,N-methyl-N-(2-methylpropyl)aminocarbonyl,N-(1,1-dimethylethyl)-N-methylaminocarbonyl,N-ethyl-N-propylaminocarbonyl, N-ethyl-N-(1-methylethyl)aminocarbonyl,N-butyl-N-ethylaminocarbonyl, N-ethyl-N-(1-methylpropyl)aminocarbonyl,N-ethyl-N-(2-methylpropyl)aminocarbonyl,N-ethyl-N-(1,1-dimethylethyl)aminocarbonyl,N-(1-methylethyl)-N-propylaminocarbonyl, N-butyl-N-propylaminocarbonyl,N-(1-methylpropyl)-N-propylaminocarbonyl,N-(2-methylpropyl)-N-propyl-aminocarbonyl,N-(1,1-dimethylethyl)-N-propylaminocarbonyl,N-butyl-N-(1-methylethyl)aminocarbonyl,N-(1-methylethyl)-N-(1-methylpropyl)aminocarbonyl,N-(1-methylethyl)-N-(2-methylpropyl)aminocarbonyl,N-(1,1-dimethylethyl)-N-(1-methylethyl)aminocarbonyl,N-butyl-N-(1-methylpropyl)aminocarbonyl,N-butyl-N-(2-methylpropyl)aminocarbonyl,N-butyl-N-(1,1-dimethylethyl)aminocarbonyl,N-(1-methylpropyl)-N-(2-methylpropyl)aminocarbonyl,N-(1,1-dimethylethyl)-N-(1-methylpropyl)aminocarbonyl orN-(1,1-dimethylethyl)-N-(2-methylpropyl)aminocarbonyl, preferablyN,N-dimethylaminocarbonyl or N,N-diethylaminocarbonyl, i.e., forexample, dimethylaminocarbonylmethyl, diethylaminocarbonylmethyl,1-(dimethylaminocarbonyl)ethyl or 2-(dimethylaminocarbonyl)ethyl;

C₁ -C₄ -alkylsulfinyl-C₁ -C₄ -alkyl: C₁ -C₄ -alkyl which is substitutedby methylsulfinyl, ethylsulfinyl, n-propylsulfinyl,1-methylethylsulfinyl, n-butylsulfinyl, 1-methylpropylsulfinyl,2-methylpropylsulfinyl or 1,1-dimethylethylsulfinyl, preferablymethylsulfinyl, i.e, for example, methylsulfinylmethyl or2-methylsulfinylethyl;

C₁ -C₄ -haloalkylsulfinyl-C₁ -C₄ -alkyl: C₁ -C₄ -alkyl as mentionedabove which as attached to it a C₁ -C₄ -alkylsulfinyl group which ispartially or fully substituted by fluorine, chlorine, and/or bromine,e.g. difluoromethylsulfinyl, trifluoromethylsulfinyl,chlorodifluoromethylsulfinyl, bromodifluoromethylsulfinyl,2-fluoroethylsulfinyl, 2-chloroethylsulfinyl, 2-bromoethylsulfinyl,2-iodoethylsulfinyl, 2,2-difluoroethylsulfinyl,2,2,2-trifluoroethylsulfinyl, 2,2,2-trichloroethylsulfinyl,2-chloro-2-fluoroethylsulfinyl, 2-chloro-2,2-difluoroethylsulfinyl,2,2-dichloro-2-fluoroethylsulfinyl, pentafluoroethylsulfinyl,2-fluoropropylsulfinyl, 3-fluoropropylsulfinyl, 2-chloropropylsulfinyl,3-chloropropylsulfinyl, 2-bromopropylsulfinyl, 3-bromopropylsulfinyl,2,2-difluoropropylsulfinyl, 2,3-difluoropropylsulfinyl,2,3-dichloropropylsulfinyl, 3,3,3-trifluoropropylsulfinyl,3,3,3-trichloropropylsulfinyl, 2,2,3,3,3-pentafluoropropylsulfinyl,heptafluoropropylsulfinyl, 1-(fluoromethyl)-2-fluoroethylsulfinyl,1-(chloromethyl)-2-chloroethylsulfinyl,1-(bromomethyl)-2-bromoethylsulfinyl, 4-fluorobutylsulfinyl,4-chlorobutylsulfinyl or 4-bromobutylsulfinyl, i.e., for example,difluoromethylsulfinylmethyl;

C₁ -C₄ -alkylsulfonyl: methylsulfonyl, ethylsulfonyl, n-propylsulfonyl,1-methylethylsulfonyl, n-butylsulfonyl, 1-methylpropylsulfonyl,2-methylpropylsulfonyl or 1,1-dimethylethylsulfonyl, in particularmethylsulfonyl or ethylsulfonyl;

C₁ -C₄ -alkylsulfonyl-C₁ -C₄ -alkyl: C₁ -C₄ -alkyl which is substitutedby C₁ -C₄ -alkylsulfonyl as mentioned above, preferably methylsulfonyl,i.e., for example, methylsulfonylmethyl or 2-methylsulfonylethyl;

C₁ -C₄ -haloalkylsulfonyl-C₁ -C₄ -alkyl: C₁ -C₄ -alkyl as mentionedabove which has attached to it a C₁ -C₄ -alkylsulfonyl group which ispartially or fully substituted by fluorine, chlorine and/or bromine,e.g. difluoromethylsulfonyl, trifluoromethylsulfonyl,chlorodifluoromethylsulfonyl, bromodifluoromethylsulfonyl,2-fluoroethylsulfonyl, 2-chloroethylsulfonyl, 2-bromoethylsulfonyl,2-iodoethylsulfonyl, 2,2-difluoroethylsulfonyl,2,2,2-trifluoroethylsulfonyl, 2,2,2-trichloroethylsulfonyl,2-chloro-2-fluoroethylsulfonyl, 2-chloro-2,2-difluoroethylsulfonyl,2,2-dichloro-2-fluoroethylsulfonyl, pentafluoroethylsulfonyl,2-fluoropropylsulfonyl, 3-fluoropropylsulfonyl, 2-chloropropylsulfonyl,3-chloropropylsulfonyl, 2-bromopropylsulfonyl, 3-bromopropylsulfonyl,2,2-difluoropropylsulfonyl, 2,3-difluoropropylsulfonyl,2,3-dichloropropylsulfonyl, 3,3,3-trifluoropropylsulfonyl,3,3,3-trichloropropylsulfonyl, 2,2,3,3,3-pentafluoropropylsulfonyl,heptafluoropropylsulfonly, 1-(fluoromethyl)-2-fluoroethylsulfonyl,1-(chloromethyl)-2-chloroethylsulfonyl,1-(bromomethyl)-2-bromoethylsulfonyl, 4-fluorobutylsulfonyl,4-chlorobutylsulfonyl, or 4-bromobutylsulfonyl, i.e., for example,2-chloroethylsulfonyl;

C₃ -C₆ -alkenyl: for example prop-2-en-1-yl, n-buten-4-yl,1-methylprop-2-en-1-yl, 2-methylprop-2-en-1-yl, 2-buten-1-yl,n-penten-3-yl, n-penten-4-yl, 1-methylbut-2-en-1-yl,2-methylbut-2-en-1-yl, 3-methylbut-2-en-1-yl, 1-methyl-but-3-en-1-yl,2-methylbut-3-en-1-yl, 3-methylbut-3-en-1-yl,1,1-dimethylprop-2-en-1-yl, 1,2-dimethylprop-2-en-1-yl,1-ethylprop-2-en-1-yl, n-hex-3-en-1-yl, n-hex-4-en-1-yl,n-hex-5-en-1-yl, 1-methylpent-3-en-1-yl, 2-methylpent-3-en-1-yl,3-methylpent-3-en-1-yl, 4-methyl-pent-3-en-1-yl ,1-methylpent-4-en-1-yl, 2-methyl-pent-4-en-1-yl, 3-methylpent-4-en-1-yl,4-methyl-pent-4-en-1-yl, 1,1-dimethylbut-2-en-1-yl,1,1-dimethylbut-3-en-1-yl, 1,2-dimethylbut-2-en-1-yl,1,2-dimethylbut-3-en-1-yl, 1,3-dimethylbut-2-en-1-yl,1,3-dimethylbut-3-en-1-yl, 2,2-dimethylbut-3-en-1-yl,2,3-dimethylbut-2-en-1-yl, 2,3-dimethylbut-3-en-1-yl,3,3-dimethylbut-2-en-1-yl, 1-ethylbut-2-en-1-yl, 1-ethylbut-3-en-1-yl,2-ethylbut-2-en-1-yl, 2-ethylbut-3-en-1-yl,1,1,2-trimethylprop-2-en-1-yl, 1-ethyl-1-methylprop-2-en-1-yl or1-ethyl-2-methylprop-2-en-1-yl, in particular prop-2-en-1-yl orn-buten-4-yl;

C₃ -C₆ -haloalkenyl: C₃ -C₆ -alkenyl as mentioned above which ispartially or fully substituted by fluorine, chlorine and/or bromine,i.e., for example, 2-chloroallyl, 3-chloroallyl, 2,3-dichloroallyl,3,3-dichloroallyl, 2,3,3-trichloroallyl, 2,3-dichlorobut-2-enyl,2-bromoallyl, 3-bromoallyl, 2,3-dibromoallyl, 3,3-dibromoallyl,2,3,3-tribromoallyl or 2,3-dibromobut-2-enyl, in particular2-chloroallyl or 3,3-dichloroallyl;

cyano-C₃ -C₆ -alkenyl: for example 3-cyanoallyl, 4-cyanobut-2-enyl,4-cyanobut-3-enyl or 5-cyanopent-4-enyl, preferably 3-cyanoallyl or4-cyanobut-2-enyl, in particular 3-cyanoallyl;

C₃ -C₄ -alkenyloxy-C₁ -C₄ -alkyl: C₁ -C₄ -alkyl which is substituted byC₃ -C₄ -alkenyloxy such as prop-2-enyloxy, n-but-2-enyloxy,n-but-3-enyloxy, 1-methylprop-2-enyloxy or 2-methylprop-2-enyloxy,preferably allyloxy, 2-methylprop-2-en-1-yloxy, but-1-en-3-yloxy,but-1-en-4-yloxy or but-2-en-1-yloxy, i.e., for example, allyloxymethyl,2-allyloxyethyl or but-1-en-4-yloxylmethyl;

C₃ -C₄ -alkenylthio-C₁ -C₄ -alkyl which is substituted by C₃ -C₄-alkenylthio such as prop-2-enylthio, n-but-2-enylthio,n-but-3-enylthio, 1-methylprop-2-enylthio or 2-methylprop-2-enylthio,preferably allylthio, 2-methylprop-2-en-1-ylthio, but-1-en-3-ylthio,but-1-en-4-ylthio or but-2-en-1-ylthio, i.e., for example,allylthiomethyl, 2-allythioethyl or but-1-en-4-ylthiomethyl;

C₃ -C₄ -alkenylsulfinyl-C₁ -C₄ -alkyl: C₁ -C₄ -alkyl which issubstituted by C₃ -C₄ -alkenylsulfinyl such as prop-2-enylsulfinyl,n-but-2-enylsulfinyl, n-but-3-enylsulfinyl, 1-methylprop-2-enylsulfinylor 2-methylprop-2-enylsulfinyl, preferably allylsulfinyl,2-methylprop-2-en-1-ylsulfinyl, but-1-en-3-ylsulfinyl,but-1-en-4-ylsulfinyl or but-2-en-1-ylsulfinyl, i.e., for example,allylsulfinylmethyl, 2-allylsulfinylethyl orbut-1-en-4-ylsulfinylmethyl;

C₃ -C₄ -alkenylsulfonyl-C₁ -C₄ -alkyl: C₁ -C₄ -alkyl which issubstituted by C₃ -C₄ -alkenylsulfonyl such as prop-2-enylsulfonyl,n-but-2-enylsulfonyl, n-but-3-enylsulfonyl, 1-methylprop-2-enylsulfonylor 2-methylprop-2-enylsulfonyl, preferably allylsulfonyl,2-methylprop-2-en-1-ylsulfonyl, but-1-en-3-ylsulfonyl,but-1-en-4-ylsulfonyl or but-2-en-1-ylsulfonyl, i.e., for example,allylsulfonylmethyl, 2-allylsulfonylethyl orbut-1-en-4-ylsulfonylmethyl;

C₃ -C₆ -alkynyl: for example propargyl, n-but-1-yn-3-yl,n-but-1-yn-4-yl, n-but-2-yn-1-yl, n-pent-1-yn-3-yl, n-pent-1-yn-4-yl,n-pent-1-yn-5-yl, n-pent-2-yn-1-yl, n-pent-2-yn-4-yl, n-pent-2-yn-5-yl,3-methyl-but-1-yn-3-yl, 3-methyl-but-1-yn-4-yl, n-hex-1-yn-3-yl,n-hex-1-yn-4-yl, n-hex-1-yn-5-yl, n-hex-1-yn-6-yl, n-hex-2-yn-1-yl,n-hex-2-yn-4-yl, n-hex-2-yn-5-yl, n-hex-2-yn-6-yl, n-hex-3-yn-1-yl,n-hex-3-yn-2-yl, 3-methylpent-1-yn-3-yl, 3-methylpent-1-yn-4-yl,3-methylpent-1-yn-5-yl, 4-methylpent-2-yn-4-yl or4-methylpent-2-yn-5-yl, in particular propargyl;

C₃ -C₆ -haloalkynyl: C₃ -C₆ -alkynyl as mentioned above which ispartially or fully substituted by fluorine, chlorine and/or bromine,i.e., for example, 1,1-difluoroprop-2-yn-1-yl, 4-fluorobut-2-yn-1-yl,4-chlorobut-2-yn-1-yl, 1,1-difluorobut-2-yn-1-yl, 5-fluoropent-3-yn-1-ylor 6-fluorohex-4-yn-1-yl;

cyano-C₃ -C₆ -alkynyl: for example 3-cyanopropargyl;

C₃ -C₄ -alkynyloxy-C₁ -C₄ -alkyl: C₁ -C₄ -alkyl which is substituted byC₃ -C₄ -alkynyloxy such as prop-2-ynyloxy, n-but-2-ynyloxy,n-but-3-ynyloxy or 1-methylprop-2-ynyloxy, preferably propargyloxy,but-1-yn-3-yloxy, but-1-yn-4-yloxy or but-2-yn-1-yloxy, i.e., forexample, propargyloxymethyl or 2-propargyloxyethyl;

C₃ -C₄ -alkynylthio-C₁ -C₄ -alkyl: C₁ -C₄ -alkyl which is substituted byC₃ -C₄ -alkynylthio such as prop-2-ynylthio, n-but-2-ynylthio,n-but-3-ynylthio or 1-methylprop-2-ynylthio, preferably propargylthio,but-1-yn-3-ylthio, but-1-yn-4-ylthio or but-2-yn-1-ylthio, i.e., forexample, propargylthiomethyl or 2-propargylthioethyl;

C₃ -C₄ -alkynylsulfinyl-C₁ -C₄ -alkyl which is substituted by C₃ -C₄-alkynylsulfinyl such as prop-2-ynylsulfinyl, n-but-2-ynylsulfinyl,n-but-3-ynylsulfinyl and 1-methylprop-2-ynylsulfinyl, preferablypropargylsulfinyl, but-1-yn-3-ylsulfinyl, but-1-yn-4-ylsulfinyl orbut-2-yn-1-ylsulfinyl, i.e., for example, propargylsulfinylmethyl or2-propargylsulfinylethyl;

C₃ -C₄ -alkynylsulfonyl-C₁ -C₄ -alkyl: C₁ -C₄ -alkyl which issubstituted by C₃ -C₄ -alkynylsulfonyl such as prop-2-ynylsulfonyl,n-but-2-ynylsulfonyl, n-but-3-ynylsulfonyl and1-methylprop-2-ynylsulfonyl, preferably propargylsulfonyl,but-1-yn-3-ylsulfonyl, but-1-yn-4-ylsulfonyl or but-2-yn-1-ylsulfonyl,i.e., for example, propargylsulfonylmethyl or 2-propargylsulfonylethyl;

C₃ -C₈ -cycloalkyl: cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl,cycloheptyl or cyclooctyl, in particular cyclopentyl or cyclohexy;

C₃ -C₈ -cycloalkyl-C₁ -C₄ -alkyl: cyclopropylmethyl, cyclobutylmethyl,cyclopentylmethyl, cyclohexylmethyl, cycloheptylmethyl,cyclooctylmethyl, 1-(cyclopropyl)ethyl, 1-(cyclobutyl)ethyl,1-(cyclopentyl)ethyl, 1-(cyclohexyl)ethyl, 1-(cycloheptylethyl,1-(cyclooctyl)ethyl, 2-cyclopropyl)ethyl, 2-(cyclobutyl)ethyl,2-(cyclopentyl)ethyl, 2-(cyclohexyl)ethyl, 2-(cycloheptyl)ethyl,2-(cyclooctyl)ethyl, 3-(cyclopropy)propyl, 3-(cyclobutyl)propyl,3-(cyclopentyl)propyl, 3-(cyclohexyl)propyl, 3-(cycloheptyl)propyl,3-(cyclooctyl)propyl, 4-(cyclopropyl)butyl, 4-(cyclobutyl)butyl,4-(cyclobutyl)butyl, 4-(cyclopentyl)butyl, 4-(cyclohexyl)-butyl,4-(cycloheptyl)butyl or 4-(cyclooctyl)butyl, in particularcyclopentylmethyl or cyclohexylmethyl;

C₃ -C₈ -cycloalkoxy-C₁ -C₄ -alkyl: cyclopropyloxymethyl,cyclobutyloxymethyl, cyclopentyloxymethyl, cyclohexyloymethyl,cycloheptyloxymethyl, cyclooctyloxymethyl, 1-(cyclopropyloxy)ethyl,1-(cyclobutyloxy)ethyl, 1-(cyclopentyloxy)ethyl, 1-(cyclohexyloxy)ethyl,1-(cycloheptyloxy)ethyl, 1-(cyclooctyloxy)ethyl,2-(cyclopropyloxy)ethyl, 2-(cyclobutyloxy)ethyl,2-(cyclopentyloxy)ethyl, 2-(cyclohexyloxy)ethyl,2-(cycloheptyloxy)ethyl, 2-(cyclooctyloxy)ethyl,3-(cyclopropyloxy)propyl, 3-(cyclobutyloxy)propyl,3-(cyclopentyloxy)propyl, 3-(cyclohexyloxy)propyl,3-(cycloheptyloxy)propyl, 3-(cyclooctyploxy)propyl,4-(cyclopropyloxy)butyl, 4-(cyclobutyloxy)butyl,4-(cyclopentyloxy)butyl, 4-(cyclohexyloxy)butyl, 4-(cycloheptyloxy)butyl4-(cycloheptyloxy)butyl or 4-(cyclooctyloxy)butyl, in particularcyclopentyloxymethyl, cyclohexyloxymethyl or 2-(cyclopentyloxy)ethyl.

3- to 7-membered heterocyclyl is to be understood as meaning bothsaturated, partially or fully unsaturated and aromatic heterocycleshaving one to three hetero atoms selected from a group consisting of

one to three nitrogen atoms,

one or two oxygen and

one or two sulfur atoms.

Examples of saturated heterocycles which can contain a carbonyl orthiocarbonyl ring member are:

oxiranyl, thiiranyl, aziridin-1-yl, aziridin-2-yl, diaziridin-1-yl,diaziridin-3-yl, oxetan-2-yl, oxetan-3yl, thietan-2-yl, thietan-3-yl,azetidin-1-yl, azetidin-2-yl, azetidin-3-yl, tetrahydrofuran-2-yl,tetrahydrofuran-3-yl, tetrahydrothiophen-2-yl, tetrahydrothiophen-3-yl,pyrrolidin-1-yl, pyrrolidin-2-yl, pyrrolidin-3-yl, 1,3-dioxolan-2-yl,1,3-dioxolan-4-yl, 1,3oxathiolan-2-yl, 1,3-oxathiolan-4-yl,1,3-oxathiolan-5-yl, 1,3-oxazolidin-2-yl, 1,3-oxazolidin-3-yl,1,3-oxazolidin-4-yl, 1,3-oxazolidin-5-yl, 1,2-oxazolidin-2-yl,1,2-oxazolidin-3-yl, 1,2-oxazolidin-4yl, 1,2-oxazolidin-5-yl,1,3-dithiolan-2-yl, 1,3-dithiolan-4-yl, pyrrolidin-1-yl,pyrrolidin-2-yl, pyrrolidin-5-yl, tetrahydropyrazol-1-yl,tetrahydropyrazol-3-yl, tetrahydropyrazol-4-yl, tetrahydropyran-2-yl,tetrahydropyran-3-yl, tetrahydropyran-4-yl, tetrahydrothiopyran-2-yl,tetrahydrothiopyran-3-yl, tetrahydropyran-4-yl, piperidin-1-yl,piperidin-2-yl, piperidin-3-yl, piperidin-4-yl, 1,3-dioxan-2-yl,1,3-dioxan-4-yl, 1,3-dioxan-5-yl, 1,4-dioxan-2-yl, 1,3-oxathian-2-yl,1,3-oxathian-4-yl, 1,3-oxathian-5-yl, 1,3-oxathian-6-yl,1,4-oxathian-2-yl, 1,4-oxathian-3-yl, morpholin-2-yl, morpholin-3-yl,morpholin-4-yl, hexahydropyridazin-1-yl, hexahydropyridazin-3-yl,hexahydropyridazin-4-yl, hexahydropyrimidin-1-yl,hexahydropyrimidin-2-yl, hexahydropyrimidin-4-yl,hexahydropyrimidin-5-yl, piperazin-1-yl, piperazin-2-yl, piperazin-3-yl,hexahydro-1,3,5-triazin-1-yl, hexahydro-1,3,5-triazin-2-yl, oxepan-2-yl,oxepan-3-yl, oxepan-4-yl, thiepan-2-yl, thiepan-3-yl, thiepan-4-yl,1,3-dioxepan-2-yl, 1,3-dioxepan-4-yl, 1,3-dioxepan-5-yl,1,3-dioxepan-6-yl, 1,3-dithiepan-2-yl, 1,3-dithiepan-2-yl,1,3-dithiepan-2-yl, 1,3-dithiepan-2-yl, 1,4-dioxepan-2-yl,1,4-dioxepan-7-yl, hexahydroazepin-1-yl, hexahydroazepin-2-yl,hexahydroazepin-3-yl, hexahydroazepin-4-yl, hexahydro-1,3-diazepin-1-yl,hexahydro-1,3-diazepin-2-yl, hexahydro-1,3-diazepin-4-yl,hexahydro-1,4-diazepin-1-yl and hexahydro-1,4-diazepin-2-yl;

Examples of unsaturated heterocycles which can contain a carbonyl orthiocarbonyl ring member are: dihydrofuran-2-yl, 1,2-oxazolin-3-yl,1,2-oxazolin-5-yl, 1,3-oxazolin-2-yl;

Preferred amongst the heteroaromatics are those having 5 or 6 members,i.e., for example, furyl such as 2-furyl and 3-furyl, thienyl such as2-thienyl and 3-thienyl, pyrrolyl such as 2-pyrrolyl and 3-pyrrolyl,isoxazolyl such as 3-isoxazolyl, 4-isoxazolyl and 5-isoxazolyl,isothiazolyl such as 3-isothiazolyl, 4-isothiazolyl and 5-isothiazolyl,pyrazolyl such as 3-pyrazolyl, 4-pyrazolyl and 5-pyrazolyl, oxazolylsuch as 2-oxazolyl, 4-oxazolyl and 5-oxazolyl, thiazolyl such as2-thiazolyl, 4-thiazolyl and 5-thiazolyl, imidazolyl such as2-imidazolyl and 4-imidazolyl, oxadiazolyl such as 1,2,4-oxadiazol-3-yl,1,2,4-oxadiazol-5-yl and 1,3,4-oxadiazol-2-yl, thiadiazolyl such as1,2,4-thiadiazol-3-yl, 1,2,4-thiadiazol-5-yl and 1,3,4-thiadiazol-2-yl,triazolyl such as 1,2,4-triazol-1-yl, 1,2,4-triazol-3-yl and1,2,4-triazol-4-yl, pyridinyl such as 2-pyridinyl, 3-pyridinyl and4-pyridinyl, pyridazinyl such as 3-pyridazinyl and 4-pyridazinyl,pyrimidinyl such as 2-pyrimidinyl, 4-pyrimidinyl and 5-pyrimidinyl,furthermore 2-pyrazinyl, 1,3,5-triazin-2-yl and 1,2,4-triazin-3-yl, inparticular pyridyl, pyrimidyl, furanyl and thienyl.

All phenyl and heterocyclic rings are preferably unsubstituted or haveattached to them a cyano, nitro, halogen, C₁ -C₄ -alkyl, C₁ -C₄-haloalkyl, C₁ -C₄ -alkoxy, C₁ -C₄ -haloalkoxy, (C₁ -C₄ -alkyl)carbonyl,(C₁ -C₄ -alkoxy)carbonyl or (C₁ -C₄ -alkyl)carbonyloxy substituent.

With a view to the use of the substituted 2-phenylpyridines I asherbicides or for the desiccation/defoliation of plants, preferredcompounds I are those where the substituents have the followingmeanings, in each case alone or in combination:

X is 1,2-ethyndiyl, ethylene, 1,2-ethyanediyl, methyleneoxymethylene,ethene-1,2-diyl, or oxymethylene which is bonded to the phenyl ring viathe hetero atom, it being possible for the last-mentioned 5 bridges tohave attached, to the carbon atom adjacent to the phosphorus, one of thefollowing substituents: cyano, halogen, C₁ -C₄ -alkyl or (C₁ -C₄-alkoxy)carbonyl; in particular --CH₂ --, --CH₂ CH₂ --, --CH₂--CH(halogen)--, --CH₂ --CH(CN)--, --CH₂ --CH(CH₃)--, --CH₂--CH(COOCH₃)--, --CH₂ --O--CH₂ --, --CH═CH--, --CH═C(halogen)--,--CH═C(CN)--, --CH═C(CH₃)--, --CH═C(COOCH₃)--, --CH₂ --CH(COOCH₃)-- or--OCH₂ --; especially preferably --CH₂ --CH(halogen)-- or--CH═C(halogen)--;

Y is oxygen; Z¹ is oxygen; Z² is oxygen;

R¹, R², R⁷ and R⁸, independently of one another, are hydrogen, C₁ -C₆-alkyl, C₁ -C₆ -haloalkyl, cyano-C₁ -C₄ -alkyl, C₁ -C₄ -alkoxy-C₁ -C₄ -alkyl, di(C₁ -C₄ -alkyl)amino-C₁ -C₄ -alkyl, C₁ -C₄ -alkylthio-C₁ -C₄-alkyl, C₁ -C₄ -alkylsulfonyl-C₁ -C₄ -alkyl, C₁ -C₄-haloalkylsulfonyl-C₁ -C₄ -alkyl, C₃ -C₆ -alkenyl, C₃ -C₆ -haloalkenyl,C₃ -C₆ -alkynyl, hydroxycarbonyl-C₁ -C₄ -alkyl, (C₁ -C₄-alkoxy)carbonyl-C₁ -C₄ -alkyl, aminocarbonyl-C₁ -C₄ -alkyl, (C₁ -C₄-alkyl)aminocarbonyl-C₁ -C₄ -alkyl, di(C₁ -C₄ -alkyl)aminocarbonyl-C₁-C₄ -alkyl, C₃ -C₈ -cycloalkyl, C₃ -C₈ -cycloalkyl-C₁ -C₄ -alkyl,phenyl, phenyl-C₁ -C₄ -alkyl or 3- to 7-membered heterocyclyl orheterocyclyl-C₁ -C₄ -alkyl, it being possible for all heterocycles, ifdesired, to contain a carbonyl or thiocarbonyl ring member and it beingpossible for all cycloalkyl, phenyl and heterocyclyl rings to beunsubstituted or to have attached to them one to four substituents, ineach case selected from the group consisting of halogen, nitro, amino,hydroxyl, carboxyl, C₁ -C₄ -alkyl, C₁ -C₄ -haloalkyl, C₁ -C₄ -alkoxy, C₁-C₄ -alkylsulfonyl, (C₁ -C₄ -alkyl)carbonyl, (C₁ -C₄ -alkoxy)carbonyland di(C₁ -C₄ -alkyl)amino,

or R¹ and R² or R¹ and R⁷ and/or R² and R⁸ in each case together form a

1,2-ethanediyl, 1,3-propylene, tetramethylene, pentamethylene orethyleneoxyethylene chain which, if desired, can be substituted by oneto four C₁ -C₄ -alkyl groups and/or one or two (C₁ -C₄ -alkoxy)carbonylgroups;

in particular hydrogen, C₁ -C₆ -alkyl, C₁ -C₆ -haloalkyl, C₃ -C₆-alkenyl, C₃ -C₆ -haloalkenyl, C₃ -C₆ -alkynyl, (C₁ -C₄-alkoxy)carbonyl-C₁ -C₄ -alkyl, C₃ -C₈ -cycloalkyl, C₃ -C₈-cycloalkyl-C₁ -C₄ -alkyl, phenyl, phenyl-C₁ -C₄ -alkyl, 3- to7-membered heterocyclyl or heterocyclyl-C₁ -C₄ -alkyl,

or R¹ and R² and/or R¹ and R⁷ and/or R² and R⁸ in each case togetherform a 1,2-ethanediyl- or 1,3-propylene chain; especially preferablyhydrogen, C₁ -C₆ -alkyl, C₃ -C₆ -alkenyl, C₃ -C₆ -alkynyl, C₃ -C₈-cycloalkyl, phenyl or phenyl-C₁ -C₄ -alkyl, or R¹ and R² together forma 1,3-propylene chain;

R³ is cyano, halogen or trifluoromethyl, in particular cyano orchlorine, especially preferably chlorine;

R⁴ is hydrogen, fluorine or chlorine, in particular hydrogen orfluorine;

R⁵ is chlorine;

R⁶ is chlorine or trifluoromethyl, in particular trifluoromethyl;

n is zero.

Very especially preferred are the compound Iaα (= I where X=methylene;R³, R⁵ =chlorine; R⁴ =hydrogen; R⁶ =trifluoromethyl; n=0) which arelisted in Table 1 below:

                  TABLE 1                                                         ______________________________________                                                                      Iaα                                        ##STR3##                                                                     No.       --P(═Y)(Z.sup.1 R.sup.1)(Z.sup.2 R.sup.2)                       ______________________________________                                        Iaα. 1                                                                            --P(═O)(OH).sub.2                                               Iaα. 2                                                                            --P(═O)(OCH.sub.3).sub.2                                        Iaα. 3                                                                            --P(═O)(OC.sub.2 H.sub.5).sub.2                                 Iaα. 4                                                                            --P(═O)[O--(n-C.sub.3 H.sub.7)].sub.2                           Iaα. 5                                                                            --P(═O)[OCH(CH.sub.3).sub.2 ].sub.2                             Iaα. 6                                                                            --P(═O)[O--(n-C.sub.4 H.sub.9)].sub.2                           Iaα. 7                                                                            --P(═O)[OCH.sub.2 --CH(CH.sub.3).sub.2 ].sub.2                  Iaα. 8                                                                            --P(═O)[OCH(CH.sub.3)--C.sub.2 H.sub.5 ].sub.2                  Iaα. 9                                                                            --P(═O)(OCH.sub.2 --CF.sub.3).sub.2                             Iaα. 10                                                                           --P(═O)(OCH.sub.2 --CH.sub.2 --OH).sub.2                        Iaα. 11                                                                           --P(═O)(OCH.sub.2 --CH.sub.2 --CN).sub.2                        Iaα. 12                                                                           --P(═O)(OCH.sub.2 --CH.sub.2 --OCH.sub.3).sub.2                 Iaα. 13                                                                           --P(═O)(OCH.sub.2 --CH.sub.2 --OC.sub.2 H.sub.5).sub.2          Iaα. 14                                                                           --P(═O)(OCH.sub.2 --CH.sub.2 --OCF.sub.3).sub.2                 Iaα. 15                                                                           --P(═O)(OCH.sub.2 --CH.sub.2 --OCH.sub.2 --CH═CH.sub.2).              sub.2                                                               Iaα. 16                                                                           --P(═O)(OCH.sub.2 --CH.sub.2 --OCH.sub.2 --C.tbd.CH).sub.2      Iaα. 17                                                                           --P(═O)(OCH.sub.2 --CH.sub.2 --O-cyclopentyl).sub.2             Iaα. 18                                                                           --P(═O)(OCH.sub.2 --CH.sub.2 --NH.sub.2).sub.2                  Iaα. 19                                                                           --P(═O)(OCH.sub.2 --CH.sub.2 --NH--CH.sub.3).sub.2              Iaα. 20                                                                           --P(═O)[OCH.sub.2 --CH.sub.2 --N(CH.sub.3).sub.2 ].sub.2        Iaα. 21                                                                           --P(═O)(OCH.sub.2 --CH.sub.2 --SCH.sub.3).sub.2                 Iaα. 22                                                                           --P(═O)(OCH.sub.2 --CH.sub.2 --SC.sub.2 H.sub.5).sub.2          Iaα. 23                                                                           --P(═O)(OCH.sub.2 --CH.sub.2 --SCF.sub.3).sub.2                 Iaα. 24                                                                           --P(═O)(OCH.sub.2 --CH.sub.2 --SCH.sub.2 --CH═CH.sub.2).              sub.2                                                               Iaα. 25                                                                           --P(═O)(OCH.sub.2 --CH.sub.2 --SCH.sub.2 --C.tbd.CH).sub.2      Iaα. 26                                                                           --P(═O)(OCH.sub.2 --CH.sub.2 --SCH.sub.2 --C.tbd.CH).sub.2      Iaα. 27                                                                           --P(═O)(OCH.sub.2 --CH.sub.2 --SO--C.sub.2 H.sub.5).sub.2       Iaα. 28                                                                           --P(═O)(OCH.sub.2 --SO.sub.2 --CH.sub.3).sub.2                  Iaα. 29                                                                           --P(═O)(OCH.sub.2 --SO.sub.2 --C.sub.2 H.sub.5).sub.2           Iaα. 30                                                                           --P(═O)(OCH.sub.2 --CH.sub.2 --SO.sub.2 --CH.sub.3).sub.2       Iaα. 31                                                                           --P(═O)(OCH.sub.2 --CH.sub.2 --SO.sub.2 --C.sub.2 H.sub.5).s              ub.2                                                                Iaα. 32                                                                           --P(═O)(OCH.sub.2 --CH═CH.sub.2).sub.2                      Iaα. 33                                                                           --P(═O)(OCH.sub.2 --CH═CH--CH.sub.3).sub.2                  Iaα. 34                                                                           --P(═O)(OCH.sub.2 --CH.sub.2 --CH═CH.sub.2).sub.2           Iaα. 35                                                                           --P(═O)(OCH.sub.2 --CH═CH--Cl).sub.2                        Iaα. 36                                                                           --P(═O)(OCH.sub.2 --C.tbd.CH).sub.2                             Iaα. 37                                                                           --P(═O)[OCH(CH.sub.3)--C.tbd.CH].sub.2                          Iaα. 38                                                                           --P(═O)(OCH.sub.2 --CO--OCH.sub.3).sub.2                        Iaα. 39                                                                           --P(═O)(OCH.sub.2 --CO--OC.sub.2 H.sub.5).sub.2                 Iaα. 40                                                                           --P(═O)[OCH(CH.sub.3)--CO--OCH.sub.3 ].sub.2                    Iaα. 41                                                                           --P(═O)[OCH(CH.sub.3)--CO--OC.sub.2 H.sub.5 ].sub.2             Iaα. 42                                                                           --P(═O)(OCH.sub.2 --CO--NH.sub.2).sub.2                         Iaα. 43                                                                           --P(═O)(OCH.sub.2 --CO--NH--CH.sub.3).sub.2                     Iaα. 44                                                                           --P(═O)[OCH.sub.2 --CO--N(CH.sub.3).sub.2 ].sub.2               Iaα. 45                                                                           --P(═O)[OCH(CH.sub.3)--CO--NH.sub.2 ].sub.2                     Iaα. 46                                                                           --P(═O)[OCH(CH.sub.3)--CO--NH--CH.sub.3 ].sub.2                 Iaα. 47                                                                           --P(═O)[OCH(CH.sub.3)--CO--N(CH.sub.3).sub.2 ].sub.2            Iaα. 48                                                                           --P(═O)(O-cyclopropyl).sub.2                                    Iaα. 49                                                                           --P(═O)(O-cyclobutyl).sub.2                                     Iaα. 50                                                                           --P(═O)(O-cyclopentyl).sub.2                                    Iaα. 51                                                                           --P(═O)(O-cyclohexyl).sub.2                                     Iaα. 52                                                                           --P(═O)(OCH.sub.2 -cyclopropyl).sub.2                           Iaα. 53                                                                           --P(═O)(OCH.sub.2 -cyclobutyl).sub.2                            Iaα. 54                                                                           --P(═O)(OCH.sub.2 -cyclopentyl).sub.2                           Iaα. 55                                                                           --P(═O)(OCH.sub.2 -cyclohexyl).sub.2                            Iaα. 56                                                                           --P(═O)(O-phenyl).sub.2                                         Iaα. 57                                                                           --P(═O)(OCH.sub.2 -phenyl).sub.2                                Iaα. 58                                                                           --P(═O)(O-oxetan-3-yl).sub.2                                    Iaα. 59                                                                           --P(═O)(O-tetrahydrofuran-2-yl).sub.2                           Iaα. 60                                                                           --P(═O)(O-tetrahydrofuran-3-yl).sub.2                           Iaα. 61                                                                           --P(═O)(O-tetrahydropyran-2-yl).sub.2                           Iaα. 62                                                                           --P(═O)(O-tetrahydropyran-3-yl).sub.2                           Iaα. 63                                                                           --P(═O)(O-tetrahydropyran-4-yl).sub.2                           Iaα. 64                                                                           --P(═O)(OCH.sub.2 -oxiran-2-yl).sub.2                           Iaα. 65                                                                           --P(═O)(OCH.sub.2 -oxetan-3-yl).sub.2                           Iaα. 66                                                                           --P(═O)(OCH.sub.2 -tetrahydrofuran-2-yl).sub.2                  Iaα. 67                                                                           --P(═O)(OCH.sub.2 -tetrahydrofuran-3-yl).sub.2                  Iaα. 68                                                                           --P(═O)(OCH.sub.2 -pyrrolidin-1-yl).sub.2                       Iaα. 69                                                                           --P(═O)[OCH.sub.2 --(2-pyrrolidon-1-yl)].sub.2                  Iaα. 70                                                                           --P(═O)(OCH.sub.2 -tetrahydropyran-2-yl).sub.2                  Iaα. 71                                                                           --P(═O)(OCH.sub.2 -tetrahydropyran-3-yl).sub.2                  Iaα. 72                                                                           --P(═O)(OCH.sub.2 -tetrahydropyran-4-yl).sub.2                  Iaα. 73                                                                           --P(═O)(OCH.sub.2 -piperidin-1-yl).sub.2                        Iaα. 74                                                                           --P(═O)(OCH.sub.2 -morpholin-4-yl).sub.2                        Iaα. 75                                                                           --P(═O)(OH)(OCH.sub.3)                                          Iaα. 76                                                                           --P(═O)(OH)(OC.sub.2 H.sub.5)                                   Iaα. 77                                                                           --P(═O)(OH)[O--[n-C.sub.3 H.sub.7)]                             Iaα. 78                                                                           --P(═O)(OH)[OCH(CH.sub.3).sub.2 ]                               Iaα. 79                                                                           --P(═O)(OH)[O--(n-C.sub.4 H.sub.9)]                             Iaα. 80                                                                           --P(═O)(OH)[OCH.sub.2 --CH(CH.sub.3).sub.2 ]                    Iaα. 81                                                                           --P(═O)(OH)[OCH(CH.sub.3)--C.sub.2 H.sub.5 ]                    Iaα. 82                                                                           --P(═O)(OH)(OCH.sub.2 --CF.sub.3)                               Iaα. 83                                                                           --P(═O)(OH)(OCH.sub.2 --CH.sub.2 --OH)                          Iaα. 84                                                                           --P(═O)(OH)(OCH.sub.2 --CH.sub.2 --CN)                          Iaα. 85                                                                           --P(═O)(OH)(OCH.sub.2 --CH.sub.2 --OCH.sub.3)                   Iaα. 86                                                                           --P(═O)(OH)(OCH.sub.2 --CH.sub.2 --OC.sub.2 H.sub.5)            Iaα. 87                                                                           --P(═O)(OH)(OCH.sub.2 --CH.sub.2 --OCF.sub.3)                   Iaα. 88                                                                           --P(═O)(OH)(OCH.sub.2 --CH.sub.2 --OCH.sub.2 --CH═CH.sub              .2)                                                                 Iaα. 89                                                                           --P(═O)(OH)(OCH.sub.2 --CH.sub.2 --OCH.sub.2 --C.tbd.CH)        Iaα. 90                                                                           --P(═O)(OH)(OCH.sub.2 --CH.sub.2 --O-cyclopentyl)               Iaα. 91                                                                           --P(═O)(OH)(OCH.sub.2 --CH.sub.2 --NH.sub.2)                    Iaα. 92                                                                           --P(═O)(OH)(OCH.sub.2 --CH.sub.2 --NH--CH.sub.3)                Iaα. 93                                                                           --P(═O)(OH)[OCH.sub.2 --CH.sub.2 --N(CH.sub.3).sub.2 ]          Iaα. 94                                                                           --P(═O)(OH)(OCH.sub.2 --CH.sub.2 --SCH.sub.3)                   Iaα. 95                                                                           --P(═O)(OH)(OCH.sub.2 --CH.sub.2 --SC.sub.2 H.sub.5)            Iaα. 96                                                                           --P(═O)(OH)(OCH.sub.2 --CH.sub.2 --SCF.sub.3)                   Iaα. 97                                                                           --P(═O)(OH)(OCH.sub.2 --CH.sub.2 --SCH.sub.2 --CH═CH.sub              .2)                                                                 Iaα. 98                                                                           --P(═O)(OH)(OCH.sub.2 --CH.sub.2 --SCH.sub.2 --C.tbd.CH)        Iaα. 99                                                                           --P(═O)(OH)(OCH.sub.2 --CH.sub.2 --SO--CH.sub.3)                Iaα. 100                                                                          --P(═O)(OH)(OCH.sub.2 --CH.sub.2 --SO--C.sub.2 H.sub.5)         Iaα. 101                                                                          --P(═O)(OH)(OCH.sub.2 --SO.sub.2 --CH.sub.3)                    Iaα. 102                                                                          --P(═O)(OH)(OCH.sub.2 --SO.sub.2 --C.sub.2 H.sub.5)             Iaα. 103                                                                          --P(═O)(OH)(OCH.sub.2 --CH.sub.2 --SO.sub.2 --CH.sub.3)         Iaα. 104                                                                          --P(═O)(OH)(OCH.sub.2 --CH.sub.2 --SO.sub.2 --C.sub.2                     H.sub.5)                                                            Iaα. 105                                                                          --P(═O)(OH)(OCH.sub.2 --CH═CH.sub.2)                        Iaα. 106                                                                          --P(═O)(OH)(OCH.sub.2 --CH═CH--CH.sub.3)                    Iaα. 107                                                                          --P(═O)(OH)(OCH.sub.2 --CH.sub.2 --CH═CH.sub.2)             Iaα. 108                                                                          --P(═O)(OH)(OCH.sub.2 --CH═CH--Cl)                          Iaα. 109                                                                          --P(═O)(OH)(OCH.sub.2 --C.tbd.CH)                               Iaα. 110                                                                          --P(═O)(OH)[OCH(CH.sub.3)--C.tbd.CH]                            Iaα. 111                                                                          --P(═O)(OH)(OCH.sub.2 --CO--OCH.sub.3)                          Iaα. 112                                                                          --P(═O)(OH)(OCH.sub.2 --CO--OC.sub.2 H.sub.5)                   Iaα. 113                                                                          --P(═O)(OH)[OCH(CH.sub.3)--CO--OCH.sub.3 ]                      Iaα. 114                                                                          --P(═O)(OH)[OCH(CH.sub.3)--CO--OC.sub.2 H.sub.5 ]               Iaα. 115                                                                          --P(═O)(OH)(OCH.sub.2 --CO--NH.sub.2)                           Iaα. 116                                                                          --P(═O)(OH)(OCH.sub.2 --CO--NH--CH.sub.3)                       Iaα. 117                                                                          --P(═O)(OH)[OCH.sub.2 --CO--N(CH.sub.3).sub.2 ]                 Iaα. 118                                                                          --P(═O)(OH)[OCH(CH.sub.3)--CO--NH.sub.2 ]                       Iaα. 119                                                                          --P(═O)(OH)[OCH(CH.sub.3)--CO--NH--CH.sub.3 ]                   Iaα. 120                                                                          --P(═O)(OH)[OCH(CH.sub.3 --CO--N(CH.sub.3).sub.2 ]              Iaα. 121                                                                          --P(═O)(OH)(O-cyclopropyl)                                      Iaα. 122                                                                          --P(═O)(OH)(O-cyclobutyl)                                       Iaα. 123                                                                          --P(═O)(OH)(O-cyclopentyl)                                      Iaα. 124                                                                          --P(═O)(OH)(O-cyclohexyl)                                       Iaα. 125                                                                          --P(═O)(OH)(OCH.sub.2 -cyclopropyl)                             Iaα. 126                                                                          --P(═O)(OH)(OCH.sub.2 -cyclobutyl)                              Iaα. 127                                                                          --P(═O)(OH)(OCH.sub.2 -cyclopentyl)                             Iaα. 128                                                                          --P(═O)(OH)(OCH.sub.2 -cyclohexyl)                              Iaα. 129                                                                          --P(═O)(OH)(O-phenyl)                                           Iaα. 130                                                                          --P(═O)(OH)(OCH.sub.2 -phenyl)                                  Iaα. 131                                                                          --P(═O)(OH)(O-oxetan-3-yl)                                      Iaα. 132                                                                          --P(═O)(OH)(O-tetrahydrofuran-2-yl)                             Iaα. 133                                                                          --P(═O)(OH)(O-tetrahydrofuran-3-yl)                             Iaα. 134                                                                          --P(═O)(OH)(O-tetrahydropyran-2-yl)                             Iaα. 135                                                                          --P(═O)(OH)(O-tetrahydropyran-3-yl)                             Iaα. 136                                                                          --P(═O)(OH)(O-tetrahydropyran-4-yl)                             Iaα. 137                                                                          --P(═O)(OH)(OCH.sub.2 -oxiran-2-yl)                             Iaα. 138                                                                          --P(═O)(OH)(OCH.sub.2 -oxetan-3-yl)                             Iaα. 139                                                                          --P(═O)(OH)(OCH.sub.2 -tetrahydrofuran-2-yl)                    Iaα. 140                                                                          --P(═O)(OH)(OCH.sub.2 -tetrahydrofuran-3-yl)                    Iaα. 141                                                                          --P(═O)(OH)(OCH.sub.2 -pyrrolidin-1-yl)                         Iaα. 142                                                                          --P(═O)(OH)[OCH.sub.2 --(2-pyrrolidon-1-yl)]                    Iaα. 143                                                                          --P(═O)(OH)(OCH.sub.2 -tetrahydropyran-2-yl)                    Iaα. 144                                                                          --P(═O)(OH)(OCH.sub.2 -tetrahydropyran-3-yl)                    Iaα. 145                                                                          --P(═O)(OH)(OCH.sub.2 -tetrahydropyran-4-yl)                    Iaα. 146                                                                          --P(═O)(OH)(OCH.sub.2 -piperidin-1-yl)                          Iaα. 147                                                                          --P(═O)(OH)(OCH.sub.2 -morpholin-4-yl)                          Iaα. 148                                                                          --P(═O)(OCH.sub.3)(OC.sub.2 H.sub.5)                            Iaα. 149                                                                          --P(═O)(OCH.sub.3)[O--(n-C.sub.3 H.sub.7)]                      Iaα. 150                                                                          --P(═O)(OCH.sub.3)[OCH(CH.sub.3).sub.2 ]                        Iaα. 151                                                                          --P(═O)(OCH.sub.3)[O--(n-C.sub.4 H.sub.9)]                      Iaα. 152                                                                          --P(═O)(OCH.sub.3)[OCH.sub.2 --CH(CH.sub.3).sub.2 ]             Iaα. 153                                                                          --P(═O)(OCH.sub.3)[OCH(CH.sub.3)--C.sub.2 H.sub.5 ]             Iaα. 154                                                                          --P(═O)(OCH.sub.3)(OCH.sub.2 --CF.sub.3)                        Iaα. 155                                                                          --P(═O)(OCH.sub.3)(OCH.sub.2 --CH.sub.2 --OH)                   Iaα. 156                                                                          --P(═O)(OCH.sub.3)(OCH.sub.2 --CH.sub.2 --CN)                   Iaα. 157                                                                          --P(═O)(OCH.sub.3)(OCH.sub.2 --CH.sub.2 --OCH.sub.3)            Iaα. 158                                                                          --P(═O)(OCH.sub.3)(OCH.sub.2 --CH.sub.2 --OC.sub.2 H.sub.5)     Iaα. 159                                                                          --P(═O)(OCH.sub.3)(OCH.sub.2 --CH.sub.2 --OCF.sub.3)            Iaα. 160                                                                          --P(═O)(OCH.sub.3)(OCH.sub.2 --CH.sub.2 --OCH.sub.2                       --CH═CH.sub.2)                                                  Iaα. 161                                                                          --P(═O)(OCH.sub.3)(OCH.sub.2 --CH.sub.2 --OCH.sub.2                       --C.tbd.CH)                                                         Iaα. 162                                                                          --P(═O)(OCH.sub.3)(OCH.sub.2 --CH.sub.2 --O-cyclopentyl)        Iaα. 163                                                                          --P(═O)(OCH.sub.3)(OCH.sub.2 --CH.sub.2 --NH.sub.2)             Iaα. 164                                                                          --P(═O)(OCH.sub.3)(OCH.sub.2 --CH.sub.2 --NH--CH.sub.3)         Iaα. 165                                                                          --P(═O)(OCH.sub.3)[OCH.sub.2 --CH.sub.2 --N(CH.sub.3).sub.2               ]                                                                   Iaα. 166                                                                          --P(═O)(OCH.sub.3)(OCH.sub.2 --CH.sub.2 --SCH.sub.3)            Iaα. 167                                                                          --P(═O)(OCH.sub.3)(OCH.sub.2 --CH.sub.2 --SC.sub.2 H.sub.5)     Iaα. 168                                                                          --P(═O)(OCH.sub.3)(OCH.sub.2 --CH.sub.2 --SCF.sub.3)            Iaα. 169                                                                          --P(═O)(OCH.sub.3)(OCH.sub.2 --CH.sub.2 --SCH.sub.2                       --CH═CH.sub.2)                                                  Iaα. 170                                                                          --P(═O)(OCH.sub.3)(OCH.sub.2 --CH.sub.2 --SCH.sub.2                       --C.tbd.CH)                                                         Iaα. 171                                                                          --P(═O)(OCH.sub.3)(OCH.sub.2 --CH.sub.2 --SO--CH.sub.3)         Iaα. 172                                                                          --P(═O)(OCH.sub.3)(OCH.sub.2 --CH.sub.2 --SO--C.sub.2                     H.sub.5)                                                            Iaα. 173                                                                          --P(═O)(OCH.sub.3)(OCH.sub.2 --SO.sub.2 --CH.sub.3)             Iaα. 174                                                                          --P(═O)(OCH.sub.3)(OCH.sub.2 --SO.sub.2 --C.sub.2 H.sub.5)      Iaα. 175                                                                          --P(═O)(OCH.sub.3)(OCH.sub.2 --CH.sub.2 --SO.sub.2 --CH.sub.              3)                                                                  Iaα. 176                                                                          --P(═O)(OCH.sub.3)(OCH.sub.2 --CH.sub.2 --SO.sub.2 --C.sub.2               H.sub.5)                                                           Iaα. 177                                                                          --P(═O)(OCH.sub.3)(OCH.sub.2 --CH═CH.sub.2)                 Iaα. 178                                                                          --P(═O)(OCH.sub.3)(OCH.sub.2 --CH═CH--CH.sub.3)             Iaα. 179                                                                          --P(═O)(OCH.sub.3)(OCH.sub.2 --CH.sub.2 --CH═CH.sub.2)      Iaα. 180                                                                          --P(═O)(OCH.sub.3)(OCH.sub.2 --CH═CH--Cl)                   Iaα. 181                                                                          --P(═O)(OCH.sub.3)(OCH.sub.2 --C.tbd.CH)                        Iaα. 182                                                                          --P(═O)(OCH.sub.3)[OCH(CH.sub.3)--C.tbd.CH]                     Iaα. 183                                                                          --P(═O)(OCH.sub.3)(OCH.sub.2 --CO--OCH.sub.3)                   Iaα. 184                                                                          --P(═O)(OCH.sub.3)(OCH.sub.2 --CO--OC.sub.2 H.sub.5)            Iaα. 185                                                                          --P(═O)(OCH.sub.3)[OCH(CH.sub.3)--CO--OCH.sub.3 ]               Iaα. 186                                                                          --P(═O)(OCH.sub.3)[OCH(CH.sub.3)--CO--OC.sub.2 H.sub.5 ]        Iaα. 187                                                                          --P(═O)(OCH.sub.3)(OCH.sub.2 --CO--NH.sub.2)                    Iaα. 188                                                                          --P(═O)(OCH.sub.3)(OCH.sub.2 --CO--NH--CH.sub.3)                Iaα. 189                                                                          --P(═O)(OCH.sub.3)(OCH.sub.2 --CO--N(CH.sub.3).sub.2 ]          Iaα. 190                                                                          --P(═O)(OCH.sub.3)[OCH(CH.sub.3)--CO--NH.sub.2 ]                Iaα. 191                                                                          --P(═O)(OCH.sub.3)[OCH(CH.sub.3)--CO--NH--CH.sub.3 ]            Iaα. 192                                                                          --P(═O)(OCH.sub.3)[OCH(CH.sub.3)--CO--N(CH.sub.3).sub.2 ]       Iaα. 193                                                                          --P(═O)(OCH.sub.3)(O-cyclopropyl)                               Iaα. 194                                                                          --P(═O)(OCH.sub.3)(O-cyclobutyl)                                Iaα. 195                                                                          --P(═O)(OCH.sub.3)(O-cyclopentyl)                               Iaα. 196                                                                          --P(═O)(OCH.sub.3)(O-cyclohexyl)                                Iaα. 197                                                                          --P(═O)(OCH.sub.3)(OCH.sub.2 -cyclopropyl)                      Iaα. 198                                                                          --P(═O)(OCH.sub.3)(OCH.sub.2 -cyclobutyl)                       Iaα. 199                                                                          --P(═O)(OCH.sub.3)(OCH.sub.2 -cyclopentyl)                      Iaα. 200                                                                          --P(═O)(OCH.sub.3)(OCH.sub.2 -cyclohexyl)                       Iaα. 201                                                                          --P(═O)(OCH.sub.3)(O-phenyl)                                    Iaα. 202                                                                          --P(═O)(OCH.sub.3)(OCH.sub.2 -phenyl)                           Iaα. 203                                                                          --P(═O)(OCH.sub.3)(O-oxetan-3-yl)                               Iaα. 204                                                                          --P(═O)(OCH.sub.3)(O-tetrahydrofuran-2-yl)                      Iaα. 205                                                                          --P(═O)(OCH.sub.3)(O-tetrahydrofuran-3-yl)                      Iaα. 206                                                                          --P(═O)(OCH.sub.3)(O-tetrahydropyran-2-yl)                      Iaα. 207                                                                          --P(═O)(OCH.sub.3)(O-tetrahydropyran-3-yl)                      Iaα. 208                                                                          --P(═O)(OCH.sub.3)(O-tetrahydropyran-4-yl)                      Iaα. 209                                                                          --P(═O)(OCH.sub.3)(OCH.sub.2 -oxiran-2-yl)                      Iaα. 210                                                                          --P(═O)(OCH.sub.3)(OCH.sub.2 -oxetan-3-yl)                      Iaα. 211                                                                          --P(═O)(OCH.sub.3)(OCH.sub.2 -tetrahydrofuran-2-yl)             Iaα. 212                                                                          --P(═O)(OCH.sub.3)(OCH.sub.2 -tetrahydrofuran-3-yl)             Iaα. 213                                                                          --P(═O)(OCH.sub.3)(OCH.sub.2 -pyrrolidin-1-yl)                  Iaα. 214                                                                          --P(═O)(OCH.sub.3)[OCH.sub.2 --(2-pyrrolidon-1-yl)              Iaα. 215                                                                          --P(═O)(OCH.sub.3)(OCH.sub.2 -tetrahydropyran-2-yl)             Iaα. 216                                                                          --P(═O)(OCH.sub.3)(OCH.sub.2 -tetrahydropyran-3-yl)             Iaα. 217                                                                          --P(═O)(OCH.sub.3)(OCH.sub.2 -tetrahydropyran-4-yl)             Iaα. 218                                                                          --P(═O)(OCH.sub.3)(OCH.sub.2 -piperidin-1-yl)                   Iaα. 219                                                                          --P(═O)(OCH.sub.3)(OCH.sub.2 -morpholin-4-yl)                   Iaα. 220                                                                          --P(═O)(OC.sub.2 H.sub.5)[O--(n-C.sub.3 H.sub.7)]               Iaα. 221                                                                          --P(═O)(OC.sub.2 H.sub.5)[OCH(CH.sub.3).sub.2 ]                 Iaα. 222                                                                          --P(═O)(OC.sub.2 H.sub.5)[O--(n-C.sub.4 H.sub.9)]               Iaα. 223                                                                          --P(═O)(OC.sub.2 H.sub.5)[OCH.sub.2 --CH(CH.sub.3).sub.2 ]      Iaα. 224                                                                          --P(═O)(OC.sub.2 H.sub.5)[OCH(CH.sub.3)--C.sub.2 H.sub.5 ]      Iaα. 225                                                                          --P(═O)(OC.sub.2 H.sub.5)(OCH.sub.2 --CF.sub.3)                 Iaα. 226                                                                          --P(═O)(OC.sub.2 H.sub.5)(OCH.sub.2 --CH.sub.2 --OH)            Iaα. 227                                                                          --P(═O)(OC.sub.2 H.sub.5)(OCH.sub.2 --CH.sub.2 --CN)            Iaα. 228                                                                          --P(═O)(OC.sub.2 H.sub.5)(OCH.sub.2 --CH.sub.2 --OCH.sub.3)     Iaα. 229                                                                          --P(═O)(OC.sub.2 H.sub.5)(OCH.sub.2 --CH.sub.2 --OC.sub.2                 H.sub.5)                                                            Iaα. 230                                                                          --P(═O)(OC.sub.2 H.sub.5)(OCH.sub.2 --CH.sub.2 --OCF.sub.3)     Iaα. 231                                                                          --P(═O)(OC.sub.2 H.sub.5)(OCH.sub.2 --CH.sub.2 --OCH.sub.2                --CH═CH.sub.2)                                                  Iaα. 232                                                                          --P(═O)(OC.sub.2 H.sub.5)(OCH.sub.2 --CH.sub.2 --OCH.sub.2                --C.tbd.CH)                                                         Iaα. 233                                                                          --P(═O)(OC.sub.2 H.sub.5)(OCH.sub.2 --CH.sub.2 --O-cyclopent              yl)                                                                 Iaα. 234                                                                          --P(═O)(OC.sub.2 H.sub.5)(OCH.sub.2 --CH.sub.2 --NH.sub.2)      Iaα. 235                                                                          --P(═O)(OC.sub.2 H.sub.5)(OCH.sub.2 --CH.sub.2 --NH--CH.sub.              3)                                                                  Iaα. 236                                                                          --P(═O)(OC.sub.2 H.sub.5)[OCH.sub.2 --CH.sub.2 --N(CH.sub.3)              .sub.2 ]                                                            Iaα. 237                                                                          --P(═O)(OC.sub.2 H.sub.5)(OCH.sub.2 --CH.sub.2 --SCH.sub.3)     Iaα. 238                                                                          --P(═O)(OC.sub.2 H.sub.5)(OCH.sub.2 --CH.sub.2 --SC.sub.2                 H.sub.5)                                                            Iaα. 239                                                                          --P(═O)(OC.sub.2 H.sub.5)(OCH.sub.2 --CH.sub.2 --SCF.sub.3)     Iaα. 240                                                                          --P(═O)(OC.sub.2 H.sub.5)(OCH.sub.2 --CH.sub.2 --SCH.sub.2                --CH═CH.sub.2)                                                  Iaα. 241                                                                          --P(═O)(OC.sub.2 H.sub.5)(OCH.sub.2 --CH.sub.2 --SCH.sub.2                --C.tbd.CH)                                                         Iaα. 242                                                                          --P(═O)(OC.sub.2 H.sub.5)(OCH.sub.2 --CH.sub.2 --SO--CH.sub.              3)                                                                  Iaα. 243                                                                          --P(═O)(OC.sub.2 H.sub.5)(OCH.sub.2 --CH.sub.2 --SO--C.sub.2               H.sub.5)                                                           Iaα. 244                                                                          --P(═O)(OC.sub.2 H.sub.5)(OCH.sub.2 --SO.sub.2 --CH.sub.3)      Iaα. 245                                                                          --P(═O)(OC.sub.2 H.sub.5)(OCH.sub.2 --SO.sub.2 --C.sub.2                  H.sub.5)                                                            Iaα. 246                                                                          --P(═O)(OC.sub.2 H.sub.5)(OCH.sub.2 --CH.sub.2 --SO.sub.2                 --CH.sub.3)                                                         Iaα. 247                                                                          --P(═O)(OC.sub.2 H.sub.5)(OCH.sub.2 --CH.sub.2 --SO.sub.2                 --C.sub.2 H.sub.5)                                                  Iaα. 248                                                                          --P(═O)(OC.sub.2 H.sub.5)(OCH.sub.2 --CH═CH.sub.2)          Iaα. 249                                                                          --P(═O)(OC.sub.2 H.sub.5)(OCH.sub.2 --CH═CH--CH.sub.3)      Iaα. 250                                                                          --P(═O)(OC.sub.2 H.sub.5)(OCH.sub.2 --CH.sub.2 --CH═CH.s              ub.2)                                                               Iaα. 251                                                                          --P(═O)(OC.sub.2 H.sub.5)(OCH.sub.2 --CH═CH--Cl)            Iaα. 252                                                                          --P(═O)(OC.sub.2 H.sub.5)(OCH.sub.2 --C.tbd.CH)                 Iaα. 253                                                                          --P(═O)(OC.sub.2 H.sub.5)[OCH(CH.sub.3)--C.tbd.CH]              Iaα. 254                                                                          --P(═O)(OC.sub.2 H.sub.5)(OCH.sub.2 --CO--OCH.sub.3)            Iaα. 255                                                                          --P(═O)(OC.sub.2 H.sub.5)(OCH.sub.2 --CO--OC.sub.2 H.sub.5)     Iaα. 256                                                                          --P(═O)(OC.sub.2 H.sub.5)[OCH(CH.sub.3)--CO--OCH.sub.3 ]        Iaα. 257                                                                          --P(═O)(OC.sub.2 H.sub.5)[OCH(CH.sub.3)--CO--OC.sub.2                     H.sub.5 ]                                                           Iaα. 258                                                                          --P(═O)(OC.sub.2 H.sub.5)(OCH.sub.2 --CO--NH.sub.2)             Iaα. 259                                                                          --P(═O)(OC.sub.2 H.sub.5)(OCH.sub.2 --CO--NH--CH.sub.3)         Iaα. 260                                                                          --P(═O)(OC.sub.2 H.sub.5)[OCH.sub.2 --CO--N(CH.sub.3).sub.2               ]                                                                   Iaα. 261                                                                          --P(═O)(OC.sub.2 H.sub.5)[OCH(CH.sub.3)--CO--NH.sub.2 ]         Iaα. 262                                                                          --P(═O)(OC.sub.2 H.sub.5)[OCH(CH.sub.3)--CO--NH--CH.sub.3                 ]                                                                   Iaα. 263                                                                          --P(═O)(OC.sub.2 H.sub.5)[OCH(CH.sub.3)--CO--N(CH.sub.3).sub              .2 ]                                                                Iaα. 264                                                                          --P(═O)(OC.sub.2 H.sub.5)(O-cyclopropyl)                        Iaα. 265                                                                          --P(═O)(OC.sub.2 H.sub.5)(O-cyclobutyl)                         Iaα. 266                                                                          --P(═O)(OC.sub.2 H.sub.5)(O-cyclopentyl)                        Iaα. 267                                                                          --P(═O)(OC.sub.2 H.sub.5)(O-cyclohexyl)                         Iaα. 268                                                                          --P(═O)(OC.sub.2 H.sub.5)(OCH.sub.2 -cyclopropyl)               Iaα. 269                                                                          --P(═O)(OC.sub.2 H.sub.5)(OCH.sub.2 -cyclobutyl)                Iaα. 270                                                                          --P(═O)(OC.sub.2 H.sub.5)(OCH.sub.2 -cyclopentyl)               Iaα. 271                                                                          --P(═O)(OC.sub.2 H.sub.5)(OCH.sub.2 -cyclohexyl)                Iaα. 272                                                                          --P(═O)(OC.sub.2 H.sub.5)(O-phenyl)                             Iaα. 273                                                                          --P(═O)(OC.sub.2 H.sub.5)(OCH.sub.2 -phenyl)                    Iaα. 274                                                                          --P(═O)(OC.sub.2 H.sub.5)(O-oxetan-3-yl)                        Iaα. 275                                                                          --P(═O)(OC.sub.2 H.sub.5)(O-tetrahydrofuran-2-yl)               Iaα. 276                                                                          --P(═O)(OC.sub.2 H.sub.5)(O-tetrahydrofuran-3-yl)               Iaα. 277                                                                          --P(═O)(OC.sub.2 H.sub.5)(O-tetrahydropyran-2-yl)               Iaα. 278                                                                          --P(═O)(OC.sub.2 H.sub.5)(O-tetrahydropyran-3-yl)               Iaα. 279                                                                          --P(═O)(OC.sub.2 H.sub.5)(O-tetrahydropyran-4-yl)               Iaα. 280                                                                          --P(═O)(OC.sub.2 H.sub.5)(OCH.sub.2 -oxiran-2-yl)               Iaα. 281                                                                          --P(═O)(OC.sub.2 H.sub.5)(OCH.sub.2 -oxetan-3-yl)               Iaα. 282                                                                          --P(═O)(OC.sub.2 H.sub.5)(OCH.sub.2 -tetrahydrofuran-2-yl)      Iaα. 283                                                                          --P(═O)(OC.sub.2 H.sub.5)(OCH.sub.2 -tetrahydrofuran-3-yl)      Iaα. 284                                                                          --P(═O)(OC.sub.2 H.sub.5)(OCH.sub.2 -pyrrolidin-1-yl)           Iaα. 285                                                                          --P(═O)(OC.sub.2 H.sub.5)[OCH.sub.2 --(2-pyrrolidon-1-yl)]      Iaα. 286                                                                          --P(═O)(OC.sub.2 H.sub.5)(OCH.sub.2 -tetrahydropyran-2-yl)      Iaα. 287                                                                          --P(═O)(OC.sub.2 H.sub.5)(OCH.sub.2 -tetrahydropyran-3-yl)      Iaα. 288                                                                          --P(═O)(OC.sub.2 H.sub.5)(OCH.sub.2 -tetrahydropyran-4-yl)      Iaα. 289                                                                          --P(═O)(OC.sub.2 H.sub.5)(OCH.sub.2 -piperidin-1-yl)            Iaα. 290                                                                          --P(═O)(OC.sub.2 H.sub.5)(OCH.sub.2 -morpholin-4-yl)            Iaα. 291                                                                          --P(═O)(1,2-phenylenedioxy)                                     Iaα. 292                                                                          --P(═O)(O--CH.sub.2 --CH.sub.2 --O)                             Iaα. 293                                                                          --P(═O)[O--CH(CH.sub.3)--CH.sub.2 --O]                          Iaα. 294                                                                          --P(═O)[O--CH(CH.sub.3)--CH(CH.sub.3)--O]                       Iaα. 295                                                                          --P(═O)[O--CH(COOCH.sub.3)--CH(COOCH.sub.3)--O]                 Iaα. 296                                                                          --P(═O)(O--CH.sub.2 --CH.sub.2 --CH.sub.2 --O)                  Iaα. 297                                                                          --P(═O)[O--CH.sub.2 --C(CH.sub.3).sub.2 --CH.sub.2 --O]         Iaα. 298                                                                          --P(═O)(O--CH.sub.2 --CH.sub.2 --CH.sub.2 --CH.sub.2 --O)       Iaα. 299                                                                          --P(═S)(OH).sub.2                                               Iaα. 300                                                                          --P(═S)(OCH.sub.3).sub.2                                        Iaα. 301                                                                          --P(═S)(OC.sub.2 H.sub.5).sub.2                                 Iaα. 302                                                                          --P(═S)[O--(n-C.sub.3 H.sub.7)].sub.2                           Iaα. 303                                                                          --P(═S)[O--(n-C.sub.4 H.sub.9)].sub.2                           Iaα. 304                                                                          --P(═S)(O--CH.sub.2 --CH.sub.2 --CH.sub.2 --O)                  Iaα. 305                                                                          --P(═O)(NH.sub.2).sub.2                                         Iaα. 306                                                                          --P(═O)(NH--CH.sub.3).sub.2                                     Iaα. 307                                                                          --P(═O)[N(CH.sub.3).sub.2 ].sub.2                               Iaα. 308                                                                          --P(═O)(NH--C.sub.2 H.sub.5).sub.2                              Iaα. 309                                                                          --P(═O)[N(C.sub.2 H.sub.5).sub.2 ].sub.2                        Iaα. 310                                                                          --P(═O)(NH--CH.sub.2 --CH═CH.sub.2).sub.2                   Iaα. 311                                                                          --P(═O)(NH--CH.sub.2 --C.tbd.CH).sub.2                          Iaα. 312                                                                          --P(═O)(NH-cyclopropyl).sub.2                                   Iaα. 313                                                                          --P(═O)(NH--CH.sub.2 -cyclopentyl).sub.2                        Iaα. 314                                                                          --P(═O)(NH-phenyl).sub.2                                        Iaα. 315                                                                          --P(═O)(NH--CH.sub.2 -phenyl).sub.2                             Iaα. 316                                                                          --P(═O)(pyrrolidin-1-yl).sub.2                                  Iaα. 317                                                                          --P(═O)(2-methoxycarbonylpyrrolidin-1-yl).sub.2                 Iaα. 318                                                                          --P(═O)(NH--CH.sub.2 --CO--OCH.sub.3).sub.2                     Iaα. 319                                                                          --P(═O)[N(CH.sub.3)--CH.sub.2 --CO--OCH.sub.3 ].sub.2           Iaα. 320                                                                          --P(═O)(NH--CH.sub.2 --CO--OC.sub.2 H.sub.5).sub.2              Iaα. 321                                                                          --P(═O)[N(CH.sub.3)--CH.sub.2 --CO--OC.sub.2 H.sub.5                      ].sub.2                                                             Iaα. 322                                                                          --P(═O)[NH--CH(CH.sub.3)--CO--OCH.sub.3 ].sub.2                 Iaα. 323                                                                          --P(═O)(OH)(NH.sub.2)                                           Iaα. 324                                                                          --P(═O)(OH)(NH--CH.sub.3)                                       Iaα. 325                                                                          --P(═O)(OH)[N(CH.sub.3).sub.2 ]                                 Iaα. 326                                                                          --P(═O)(OH)(NH--C.sub.2 H.sub.5)                                Iaα. 327                                                                          --P(═O)(OH)[N(C.sub.2 H.sub.5).sub.2 ]                          Iaα. 328                                                                          --P(═O)(OH)(NH----CH.sub.2 --CH═CH.sub.2)                   Iaα. 329                                                                          --P(═O)(OH)(NH--CH.sub.2 --C.tbd.CH)                            Iaα. 330                                                                          --P(═O)(OH)(NH-cyclopropyl)                                     Iaα. 331                                                                          --P(═O)(OH)(NH--CH.sub.2 -cyclopentyl)                          Iaα. 332                                                                          --P(═O)(OH)(NH-phenyl)                                          Iaα. 333                                                                          --P(═O)(OH)(NH--CH.sub.2 -phenyl)                               Iaα. 334                                                                          --P(═O)(OH)(pyrrolidin-1-yl)                                    Iaα. 335                                                                          --P(═O)(OH)(2-methoxycarbonylpyrrolidin-1-yl)                   Iaα. 336                                                                          --P(═O)(OH)(NH--CH.sub.2 --CO--OCH.sub.3)                       Iaα. 337                                                                          --P(═O)(OH)[N(CH.sub.3)--CH.sub.2 --CO--OCH.sub.3 ]             Iaα. 338                                                                          --P(═O)(OH)(NH--CH.sub.2 --CO--OC.sub.2 H.sub.5)                Iaα. 339                                                                          --P(═O)(OH)[N(CH.sub.3)--CH.sub.2 --CO--OC.sub.2 H.sub.5 ]      Iaα. 340                                                                          --P(═O)(OH)[NH--CH(CH.sub.3)--CO--OCH.sub.3 ]                   Iaα. 341                                                                          --P(═O)(OCH.sub.3)(NH.sub.2)                                    Iaα. 342                                                                          --P(═O)(OCH.sub.3)(NH--CH.sub.3)                                Iaα. 343                                                                          --P(═O)(OCH.sub.3)[N(CH.sub.3).sub.2 ]                          Iaα. 344                                                                          --P(═O)(OCH.sub.3)(NH--C.sub.2 H.sub.5)                         Iaα. 345                                                                          --P(═O)(OCH.sub.3)[N(C.sub.2 H.sub.5).sub.2 ]                   Iaα. 346                                                                          --P(═O)(OCH.sub.3)(NH--CH.sub.2 --CH═CH.sub.2)              Iaα. 347                                                                          --P(═O)(OCH.sub.3)(NH--CH.sub.2 --C.tbd.CH)                     Iaα. 348                                                                          --P(═O)(OCH.sub.3)(NH-cyclopropyl)                              Iaα. 349                                                                          --P(═O)(OCH.sub.3)(NH--CH.sub.2 -cyclopentyl)                   Iaα. 350                                                                          --P(═O)(OCH.sub.3)(NH-phenyl)                                   Iaα. 351                                                                          --P(═O)(OCH.sub.3)(NH--CH.sub.2 -phenyl)                        Iaα. 352                                                                          --P(═O)(OCH.sub.3)(pyrrolidin-1-yl)                             Iaα. 353                                                                          --P(═O)(OCH.sub.3)(2-methoxycarbonylpyrrolidin-1-yl)            Iaα. 354                                                                          --P(═O)(OCH.sub.3)(NH--CH.sub.2 --CO--OCH.sub.3)                Iaα. 355                                                                          --P(═O)(OCH.sub.3)[N(CH.sub.3)--CH.sub.2 --CO--OCH.sub.3 ]      Iaα. 356                                                                          --P(═O)(OCH.sub.3)(NH--CH.sub.2 --CO--OC.sub.2 H.sub.5)         Iaα. 357                                                                          --P(═O)(OCH.sub.3)[N(CH.sub.3)--CH.sub.2 --CO--OC.sub.2                   H.sub.5 ]                                                           Iaα. 358                                                                          --P(═O)(OCH.sub.3)[NH--CH(CH.sub.3)--CO--OCH.sub.3 ]            Iaα. 359                                                                          --P(═O)(OC.sub.2 H.sub.5)(NH.sub.2)                             Iaα. 360                                                                          --P(═O)(OC.sub.2 H.sub.5)(NH--CH.sub.3)                         Iaα. 361                                                                          --P(═O)(OC.sub.2 H.sub.5)[N(CH.sub.3).sub.2 ]                   Iaα. 362                                                                          --P(═O)(OC.sub.2 H.sub.5)(NH--C.sub.2 H.sub.5)                  Iaα. 363                                                                          --P(═O)(OC.sub.2 H.sub.5)[N(C.sub.2 H.sub.5).sub.2 ]            Iaα. 364                                                                          --P(═O)(OC.sub.2 H.sub.5)(NH--CH.sub.2 --CH═CH.sub.2)       Iaα. 365                                                                          --P(═O)(OC.sub.2 H.sub.5)(NH--CH.sub.2 --C.tbd.CH)              Iaα. 366                                                                          --P(═O)(OC.sub.2 H.sub.5)(NH-cyclopropyl)                       Iaα. 367                                                                          --P(═O)(OC.sub.2 H.sub.5)(NH--CH.sub.2 -cyclopentyl)            Iaα. 368                                                                          --P(═O)(OC.sub.2 H.sub.5)(NH-phenyl)                            Iaα. 369                                                                          --P(═O)(OC.sub.2 H.sub.5)(NH--CH.sub.2 -phenyl)                 Iaα. 370                                                                          --P(═O)(OC.sub.2 H.sub.5)(pyrrolidin-1-yl)                      Iaα. 371                                                                          --P(═O)(OC.sub.2 H.sub.5)(2-methoxycarbonylpyrrolidin-1-yl)     Iaα. 372                                                                          --P(═O)(OC.sub.2 H.sub.5)(NH--CH.sub.2 --CO--OCH.sub.3)         Iaα. 373                                                                          --P(═O)(OC.sub.2 H.sub.5)[N(CH.sub.3)--CH.sub.2 --CO--OCH.su              b.3 ]                                                               Iaα. 374                                                                          --P(═O)(OC.sub.2 H.sub.5)(NH--CH.sub.2 --CO--OC.sub.2                     H.sub.5)                                                            Iaα. 375                                                                          --P(═O)(OC.sub.2 H.sub.5)[N(CH.sub.3)--CH.sub.2 --CO--OC.sub              .2 H.sub.5 ]                                                        Iaα. 376                                                                          --P(═O)(OC.sub.2 H.sub.5)[NH--CH(CH.sub.3)--CO--OCH.sub.3                 ]                                                                   Iaα. 377                                                                          --P(═O)[N(CH.sub.3).sub.2 ](OCH.sub.3)                          Iaα. 378                                                                          --P(═O)[N(CH.sub.3).sub.2 ](OC.sub.2 H.sub.5)                   Iaα. 379                                                                          --P(═O)[N(CH.sub.3).sub.2 ][O--(n-C.sub.3 H.sub.7)]             Iaα. 380                                                                          --P(═O)[N(CH.sub.3).sub.2 ][OCH(CH.sub.3).sub.2 ]               Iaα. 381                                                                          --P(═O)[N(CH.sub.3).sub.2 ][O--(n-C.sub.4 H.sub.9)]             Iaα. 382                                                                          --P(═O)[N(CH.sub.3).sub.2 ](OCH.sub.2 --CH═CH.sub.2)        Iaα. 383                                                                          --P(═O)[N(CH.sub.3).sub.2 ](OCH.sub.2 --C.tbd.CH)               Iaα. 384                                                                          --P(═O)[N(CH.sub.3).sub.2 ](O-cyclohexyl)                       Iaα. 385                                                                          --P(═O)[N(CH.sub.3).sub.2 ](OCH.sub.2 -cyclohexyl)              Iaα. 386                                                                          --P(═O)[N(CH.sub.3).sub.2 ](O-phenyl)                           Iaα. 387                                                                          --P(═O)[N(CH.sub.3).sub.2 ](OCH.sub.2 -phenyl)                  Iaα. 388                                                                          --P(═O)[N(CH.sub.3).sub.2 ](O-tetrahydrofuran-2-yl)             Iaα. 389                                                                          --P(═O)[N(CH.sub.3).sub.2 ](OCH.sub.2 -oxetan-3-yl)             Iaα. 390                                                                          --P(═O)[N(CH.sub.3).sub.2 ](OCH.sub.2 --CF.sub.3)               Iaα. 391                                                                          --P(═O)[N(CH.sub.3).sub.2 ](OCH.sub.2 --CO--OCH.sub.3)          Iaα. 392                                                                          --P(═O)[N(CH.sub.3).sub.2 ](OCH.sub.2 --CO--OC.sub.2                      H.sub.5)                                                            Iaα. 393                                                                          --P(═O)(NH--CH.sub.2 --CH.sub.2 --O)                            Iaα. 394                                                                          --P(═O)(NH--CH.sub.2 --CH.sub.2 --NH)                           Iaα. 395                                                                          --P(═O)[N(CH.sub.3)--CH.sub.2 --CH.sub.2 --N(CH.sub.3)]         Iaα. 396                                                                          --P(═O)(NH--CH.sub.2 --CH.sub.2 --CH.sub.2 --O)                 Iaα. 397                                                                          --P(═O)(NH--CH.sub.2 --CH.sub.2 --CH.sub.2 --NH)                Iaα. 398                                                                          --P(═O)[N(CH.sub.3)--CH.sub.2 --CH.sub.2 --CH.sub.2                       --N(CH.sub.3)]                                                      Iaα. 399                                                                          --P(═O)[O--CH.sub.2 --CH(CH.sub.3)--CH.sub.2 --O]               Iaα. 400                                                                          --P(═O)[NH--CH.sub.2 --CH.sub.2 --CH.sub.2 --N(CH.sub.3 ]       Iaα. 401                                                                          --P(═O)[N(CH.sub.3)--CH.sub.2 --C(CH.sub.3).sub.2 --CH.sub.2               --N(CH.sub.3 ]                                                     Iaα. 402                                                                          --P(═O)[NH--CH.sub.2 --CH.sub.2 --CH.sub.2 --CH.sub.2 --O]      Iaα. 403                                                                          --P(═O)[NH--CH.sub.2 --CH.sub.2 --CH.sub.2 --CH.sub.2                     --NH]                                                               Iaα. 404                                                                          --P(═S)(NH.sub.2).sub.2                                         Iaα. 405                                                                          --P(═S)(NH--CH.sub.3).sub.2                                     Iaα. 406                                                                          --P(═S)[N(CH.sub.3).sub.2 ].sub.2                               Iaα. 407                                                                          --P(═S)(NH--C.sub.2 H.sub.5).sub.2                              Iaα. 408                                                                          --P(═S)[N(C.sub.2 H.sub.5).sub.2 ].sub.2                        Iaα. 409                                                                          --P(═S)(NH--CH.sub.2 --CH.sub.2 --CH.sub.2 --O)                 Iaα. 410                                                                          --P(═S)(NH--CH.sub.2 --CH.sub.2 --CH.sub.2 --NH)                Iaα. 411                                                                          --P(═S)[N(CH.sub.3)--CH.sub.2 --CH.sub.2 --CH.sub.2                       --N(CH.sub.3)]                                                      Iaα. 412                                                                          --P(═O)(SCH.sub.3).sub.2                                        Iaα. 413                                                                          --P(═O)(SC.sub.2 H.sub.5).sub.2                                 Iaα. 414                                                                          --P(═O)[S--(n-C.sub.3 H.sub.7)].sub.2                           Iaα. 415                                                                          --P(═O)[SCH(CH.sub.3).sub.2 ].sub.2                             Iaα. 416                                                                          --P(═O)[S--(n-C.sub.4 H.sub.9)].sub.2                           Iaα. 417                                                                          --P(═O)(SCH.sub.2 --CH═CH.sub.2).sub.2                      Iaα. 418                                                                          --P(═O)(S-phenyl).sub.2                                         Iaα. 419                                                                          --P(═O)(SCH.sub.2 -phenyl).sub.2                                Iaα. 420                                                                          --P(═O)(SCH.sub.2 --CO--OCH.sub.3).sub.2                        Iaα. 421                                                                          --P(═O)(SCH.sub.2 --CO--OC.sub.2 H.sub.5).sub.2                 Iaα. 422                                                                          --P(═O)(S--CH.sub.2 --CH.sub.2 --CH.sub.2 --S)                  Iaα. 423                                                                          --P(═O)(S--CH.sub.2 --CH.sub.2 --CH.sub.2 --O)                  Iaα. 424                                                                          --P(═S)(SCH.sub.3).sub.2                                        Iaα. 425                                                                          --P(═S)(SC.sub.2 H.sub.5).sub.2                                 Iaα. 426                                                                          --P(═S)[S--(n-C.sub.3 H.sub.7)].sub.2                           Iaα. 427                                                                          --P(═S)[S-n-C.sub.4 H.sub.9)].sub.2                             Iaα. 428                                                                          --P(═S)(S--CH.sub.2 --CH.sub.2 --CH.sub.2 --S)                  Iaα. 429                                                                          --P(═S)(S--CH.sub.2 --CH.sub.2 --CH.sub.2 --O)                  ______________________________________                                    

Furthermore, the following substituted 2-phenylpyridines of the formulaeIaβ-Ioγ are especially preferred, in particular

the compounds Iaβ.1-Iaβ.429, which differ from the correspondingcompounds Iaα. 1-Iaα.429 only by the fact that R⁴ is chlorine: ##STR4##the compounds Iaγ.1-Iaγ.429, which differ from the correspondingcompounds Iaα. 1-Iaα.429 only by the fact that R⁴ is fluorine: ##STR5##the compounds Ibα.1-Ibα.429, which differ from the correspondingcompounds Iaα.1-Iaα.429 only by the fact that X is 1,2-ethanediyl:##STR6## the compounds Ibβ.1-Ibβ.429, which differ from thecorresponding compounds Iaα.1-Iaα.429 only by the fact that X is1,2-ethanediyl and R⁴ is chlorine: ##STR7## the compounds Ibγ.1-Ibγ.429,which differ from the corresponding compounds Iaα.1-Iaα.429 only by thefact that X is 1,2-ethanediyl and R⁴ is fluorine: ##STR8## the compoundsIcα.1-Icα.429, which differ from the corresponding compoundsIaα.1-Iaα.429 only by the fact that X is --CH₂ --CH(Cl)--: ##STR9## thecompounds Icβ.1-Icβ.429, which differ from the corresponding compoundsIaα.1-Iaα.429 only by the fact that X is --CH₂ --CH(Cl)-- and R⁴ ischlorine: ##STR10## the compounds Icγ.1-Icγ. 429, which differ from thecorresponding compounds Iaα.1-Iaα.429 only by the fact that X is --CH₂--CH(Cl)-- and R⁴ is fluorine: ##STR11## the compounds Idα.1-Idα. 429,which differ from the corresponding compounds Iaα.1-Iaα.429 only by thefact that X is --CH₂ --CH(Br)--: ##STR12## the compounds Idβ.1-Idβ.429,which differ from the corresponding compounds Iaα.1-Iaα.429 only by thefact that X is --CH₂ --CH(Br)-- and R⁴ is chlorine: ##STR13## thecompounds Idγ.1-Idγ.429, which differ from the corresponding compoundsIaα.1-Iaα.429 only by the fact that X is --CH₂ --CH(Br)-- and R⁴ isfluorine: ##STR14## the compounds Ieα.1-Ieα.429, which differ from thecorresponding compounds Iaα.1-Iaα.429 only by the fact that X is --CH₂--CH(CH₃)--: ##STR15## the compounds Ieβ.1-Ieβ.429, which differ fromthe corresponding compounds Iaα.1-Iaα.429 only by the fact that X is--CH₂ --CH(CH₃)-- and R⁴ is chlorine: ##STR16## the compoundIeγ.1-Ieγ.429, which differ from the corresponding compoundsIaα.1-Iaα.429 only by the fact that X is --CH₂ --CH(CH₃)-- and R⁴ isfluorine: ##STR17## the compounds Ifα.1-Ifα.429, which differ from thecorresponding compounds Iaα.1-Iaα.429 only by the fact that X is --CH₂--CH(CN)--: ##STR18## the compounds Ifβ.1-Ifβ.429, which differ from thecorresponding compounds Iaα.1-Iaα.429 only by the fact that X is --CH₂--CH(CN)-- and R⁴ is chlorine: ##STR19## the compounds Ifγ.1-Ifγ.429,which differ from the corresponding compounds Iaα.1-Iaα.429 only by thefact that X is --CH₂ CH(CN)-- and R⁴ is fluorine: ##STR20## thecompounds Igα.1-Igα.429, which differ from the corresponding compoundsIaα.1-Iaα.429 only by the fact that X is --CH₂ --CH(COOCH₃)--: ##STR21##the compounds Igβ.1-Igβ. 429, which differ from the correspondingcompounds Iaα.1-Iaα.429 only by the fact that X is --CH₂ --CH(COOCH₃)--and R⁴ is chlorine: ##STR22## the compounds Igγ.1-Igγ.429, which differfrom the corresponding compounds Iaα.1-Iaα.429 only by the fact that Xis --CH₂ --CH(COOCH₃)-- and R⁴ is fluorine: ##STR23## the compoundsIhα.1-Ihα.429, which differ from the corresponding compoundsIaα.1-Iaα.429 only by the fact that X is ethene-1,2-diyl: ##STR24## thecompounds Ihβ.1-Ihβ.429, which differ from the corresponding compoundsIaα.1-Iaα.429 only by the fact that X is ethene-1,2-dyl and R⁴ ischlorine: ##STR25## the compounds Ihγ.1-Ihγ.429, which differ from thecorresponding compounds Iaα.1-Iaα.429 only by the fact that X isethene-1,2-dyl and R⁴ is fluorine: ##STR26## the compoundsIiα.1-Iiα.429, which differ from the corresponding compoundsIaα.1-Iaα.429 only by the fact that X is --CH═C(Cl)--: ##STR27## thecompounds Iiβ.1-Iiβ.429, which differ from the corresponding compoundsIaα.1-Iaα.429 only by the fact that X is --CH═C(Cl)-- and R⁴ ischlorine: ##STR28## the compounds Iiγ.1-Iiγ.429, which differ from thecorresponding compounds Iaα.1-Iaα.429 only by the fact that X is--CH═C(Cl)-- and R⁴ is fluorine: ##STR29## the compounds Ijα.1-Ijα.429,which differ from the corresponding compounds Iaα.1-Iaα.429 only by thefact that X is --CH═C(Br)--: ##STR30## the compound Ijβ.1-Ijβ.429, whichdiffer from the corresponding compounds Iaα. 1-Iaα.429 only by the factthat X is --CH═C(Br)-- and R⁴ is chlorine: ##STR31## the compound Ijγ.1-Ijγ.429, which differ from the corresponding compounds Iaα.1-Iaα.429only by the fact that X is --CH═C(Br)-- and R⁴ is fluorine: ##STR32##the compounds Ikα.1-Ikα.429, which differ from the correspondingcompounds Iaα.1-Iaα.429 only by the fact that X is --CH═C(CH₃)--:##STR33## the compounds Ikβ.1-Ikβ.429, which differ from thecorresponding compounds Iaα.1-Iaα. 429 only by the fact that X is--CH═C(CH₃)-- and R⁴ is chlorine: ##STR34## the compounds Ikγ.1-Ikγ.429, which differ from the corresponding compounds Iaα.1-Iaα.429 only bythe fact that X is --CH═C(CH₃)-- and R⁴ is fluorine: ##STR35## thecompounds Ilα.1-Ilα.429, which differ from the corresponding compoundsIaα.1-Iaα.429 only by the fact that X is --CH═C(CN)--: ##STR36## thecompounds Ilβ.1-Ilβ.429, which differ from the corresponding compoundsIaα.1-Iaα. 429 only by the fact that X is --CH═C(CN)-- and R⁴ ischlorine: ##STR37## the compounds Ilγ.1-Ilγ.429, which differ from thecorresponding compounds Iaα.1-Iaα.429 only by the fact that X is--CH═C(CN)-- and R⁴ is fluorine: ##STR38## the compound Imα.1-Imα.429,which differ from the corresponding compounds Iaα.1-Iaα.429 only by thefact that X is --CH═C(COOCH₃)--: ##STR39## the compound Imβ.1-Imβ.429,which differ from the corresponding compounds Iaα.1-Iaα.429 only by thefact that X is --CH═C(COOCH₃)-- and R⁴ is chlorine: ##STR40## thecompounds Imγ.1-Imγ.429, which differ from the corresponding compoundsIaα. 1-Iaα.429 only by the fact that X is --CH═C(C))CH₃)-- and R⁴ isfluorine: ##STR41## the compounds Inα.1-Inα.429, which differ from thecorresponding compounds Iaα.1-Iaα.429 only by the fact that X is--CH--OCH₂ --: ##STR42## the compounds Inβ.1-Inβ.429, which differ fromthe corresponding compounds Iaα.1-Iaα.429 only by the fact that X is--CH--OCH₂ -- and R⁴ is chlorine: ##STR43## the compounds Inγ.1-Inγ.429,which differ from the corresponding compounds Iaα.1-Iaα.429 only by thefact that X is --CH--OCH₂ -- and R⁴ is fluorine: ##STR44## the compoundsIoα.1-Ioα.429, which differ from the corresponding compoundsIaα.1-Iaα.429 only by the fact that X is --OCH₂ --: ##STR45## thecompounds Ioβ.1-Ioβ.429, which differ from the corresponding compoundsIaα.1-Iaα.429 only by the fact that X is --OCH₂ -- and R⁴ is chlorine:##STR46## the compounds Ioγ.1-Ioγ. 429, which differ from thecorresponding compounds Iaα.1-Iaα.429 only by the fact that X is --OCH₂-- and R⁴ is fluorine: ##STR47##

The substituted 2-phenylpyridines of the formula I are accessible invarious ways, in particular by one of the following processes:

A) By linking the phosphonyl group with the phenylpyridine moiety

A.1) by diazotizing 3-pyridylanilines II and reacting the resultingdiazonium salts with vinyl- or alkynylphosphonic acid derivatives III bythe method of Meerwein {cf., for example, Org. Reactions 11, (1960),chapter 3, pp. 189-260 and Kogyo Kagaku Zasshi 67(12), (1964),2093-2095}: ##STR48##

In this method, the 3-pyridylaniline of the formula II, which is eitherknown from the literature or can be prepared similarly to anilines knownfrom the literature, is first converted in a manner known per se to givethe corresponding diazonium cation, and this is then reacted fully withIIIa or IIIb in the presence of a copper salt.

The diazonium salt is generally obtained by reacting the3-pyridylaniline II with a nitrite such as sodium nitrite and potassiumnitrite in an aqueous solution of an acid, e.g. in aqueous hydrofluoricacid, hydrochloric acid, hydrobromic acid, sulfuric acid ortetrafluoroboric acid. The nitrite is normally employed in approximatelyfive times the molar amount based on the amount of 3-pyridylaniline II.

The resulting solution of the diazonium salt, or the diazonium saltisolated therefrom, is then reacted with a solution or suspension of thevinyl- or alkynylphosphonic acid derivative IIa/IIb in the presence of acopper salt such as copper(I) bromide, copper(II) bromide, copper(I)chloride and copper(II) chloride.

Examples of suitable solvents are water, acetonitrile, ketones such asacetone, diethyl ketone and methyl ethyl ketone, ethers such as diethylether and tetrahydrofuran, and furthermore alcohols such as methanol orethanol.

Normally, the vinyl- or alkynylphosphonic acid derivatives IIIa/IIIb andthe copper halide are used in approximately equimolar amounts or in anexcess of up to approximately thirty times the molar amount, based onthe 3-pyridylaniline II. However, the copper halide can also be employedin smaller or catalytic amounts.

In general, the diazotization and reaction of the diazonium salt theIIIa/IIIb are carried out at from (-100) to 50° C., preferably (-20) to+30° C.

One process variant consists in adding a nitrous ester such astert-butyl nitrite and isopentyl nitrite, to a solution or suspension ofthe 3-pyridylaniline II, of the vinyl- or alkynylphosphonic acidderivative IIIa/IIIb and of the copper halide in an aqueous system, e.g.in glacial acetic acid/hydrogen chloride, absolute methanol or ethanol,in an ether such as tetrahydrofuran and dioxane or in acetonitrile oracetone. What has been said above for the reaction temperature and theproportions of the reactions also applies here.

A.2) by a Heck reaction (see, for example, A. Burini, S. Cacchi, P.Pace, B. R. Pietroni, Synlett 1995, 677): ##STR49## Regarding thedefinition of Ar, see process A.1); cat. is a transition metal catalyst,preferably a pelladium (II) compound such as palladium acetate.

In general, the reaction is carried out in an inert organic solvent, inparticular in dimethylformamide or tetrahydrofuran.

Examples of suitable bases are carbonates such as potassium carbonate,acetates such as sodium acetate and tertiary amines such astriethylamine.

The reaction is generally carried out at from 0° C. to the boiling pointof the reaction mixture, preferably at 50 to 100° C.

A.3) by Knoevenagel condensation of aromatic aldehydes VIa or ketonesVIb with phosphonic acid derivatives VII: ##STR50## As regards thedefinition of Ar, see process A.1); R^(b) is cyano, C₁ -C₄ -alkoxy or(C₁ -C₄ -alkoxy)carbonyl;

cat. is a catalyst, e.g. piperidine/acetic acid, sodium methoxide,sodium ethoxide, titanium tetrachloride/N-methylmorpholine, or chlorotri(isopropoxy) titanium/triethylamine.

The process is normally carried out in an inert organic solvent, e.g.,in an aromatic hydrocarbon such as toluene, a lower alcohol such asmethanol and ethanol or in a chlorinated hydrocarbon such asdichloromethane.

The reaction temperature is generally from 0° C. to the boiling point ofthe reaction mixture.

The water which is liberated during the reaction can be removed by meansof azeotropic distillation, if so desired. In this case, the process ispreferably carried out in an aromatic hydrocarbon such as benzene,toluene and the xylenes at the particular boiling point of the reactionmixture {see, for example, S. Abdallah-El Ayoubi, F. Texier-Boullet, J.Hamelin, Synthesis 1994, 258; D. Danion, R. Carrie, Tetrahedron Lett.1968, 4537; F. Texier-Boullet, A. Foucaud, Tetrahedron Lett. 21 (1980)2161; S. Patai, A. Schwartz, J. Org. Chem. 25 (1960), 1232; J. M.McIntosh, R. A. Sieler, Can. J. Chem. 56 (1978) 226; M. T. Reetz, R.Peter, M. v. Itzstein, Chem. Ber. 120 (1987) 121; K. A. Petrov, V. A.Chauzov, S. V. Agafonov, N. V. Pazhitnova, J. Gen. Chem. USSR 50 (1980)1225}.

Those aromatic aldehydes VIa or ketones VIb which are not already knowncan be prepared in a manner known per se.

A.4) by Wittig-Horner olefination {cf., for example, B. M. G. T. Lowen,M. R. Almond, J. Org. Chem 59 (1994) 4548; P. Teulade, P. Savignac, E.E. Aboujaoude, S. Lietge, N. Collignon, J. Organomet. Chem. 304 (1986)283; G. M. Parratt, J. Chem. Soc., Perkin Trans. 1 (1986), 1417; B.Costisella, I. Keitel H. Gross, Tetrahedron 37 (1981) 1227}: ##STR51##As regards the definition of Ar, see process A.1); R^(c) is hydrogen,halogen, C₁ -C₄ -alkyl or di(C₁ -C₄ -alkyl)amino.

The process is normally carried out in an inert organic solvent, e.g. inan aromatic hydrocarbon such as toluene, a halogenated hydrocarbon suchas dichloromethane or an ether such as diethyl ether, tetrahydrofuran,dioxane and 1,2-dimethoxyethene.

The anion VIII can be obtained, for example, by deprotonating thecorresponding methanediphorphonic acid derivative with a strong basesuch as lithium diisopropylamide, sodium hydride and n-butyllithium.

The reaction is generally carried out at from (-100)°C. to the boilingpoint of the reaction mixture, preferably at (-78) to +30° C.

A.5) by Wittig olefination {see, in this context, for example GB-A 12 43214}: ##STR52## As regards the definition of Ar, see process A.1); Ph isthe phenyl group.

The process is normally carried out in an inert organic solvent, e.g. inan aromatic hydrocarbon such as toluene, a halogenated hydrocarbon suchas dichloromethane or an ether such as diethyl ether, tetrahydrofuran,dioxane and 1,2-di-methoxyethane.

The reaction is generally carried out at from (-100)°C. to the boilingpoint of the reaction mixture, preferably at 20 to 60° C.

A.6) by Peterson olefination {see, in this context, for example O. I.Kolodyazhnyi, D. B. Golokhov, J. Gen. Chem. USSR 57 (1987) 2353; F. A.Carey, A. S. Court, J. Org. Chem. 37 (1972) 939}: ##STR53## The reactionis normally carried out in an inert organic solvent, e.g. in an aromatichydrocarbon such as toluene or an ether such as diethyl ether,tetrahydrofuran, dioxane and 1,2-dimethoxyethane.

Examples of suitable strong bases are lithium diisopropylamide, sodiumhydride or butyllithium.

The reaction is generally carried out at from (-100)°C. to the boilingpoint of the reaction mixture, preferably at (-70) to +30° C.

Those aromatic aldehydes VIa, ketones VIb and VIc and theN,N-dialkylbenzamides VId which are not already known can be prepared ina manner known per se.

A.7) by coupling a styryl halide XI with a trialkyl phosphite XII or adialkyl phosphite XIII {cf. in this context, for example, R. S. Gross,S. Mehdi, J. R. McCarthy, Tetrahedron Lett. 34 (1993) 7197; G. Axelrad,S. Laosooksathit, R. Engel, J. Org. Chem. 46 (1981) 5200}: ##STR54## Asregards the definition of Ar, see process A.1); R^(d),R^(e) arehydrogen, halogen or C₁ -C₄ -alkyl.

The process is normally carried out in an inert organic solvent,preferably in an aromatic hydrocarbon such as toluene or an ether suchas tetrahydrofuran.

The reaction of XI with a trialkyl phosphite XII is advantageouslycarried out in the presence of copper(I) bromide or copper(I) chloride.

The reaction of XI with a dialkyl phosphite XIII is advantageouslycarried out in the presence of a transition metal catalyst, preferably apalladium(II) compound such as dichlorobis(triphenylphosphine)palladium,and, if desired, in the presence of a base, e.g. triethylamine.

The reaction is generally carried out at from (-100)°C. to the boilingpoint of the reaction mixture, preferably at approximately +25° C.

Those styryl halides XI and those phosphorus compounds XII and XIIIwhich are not already known can be prepared in a manner known per se.

A.8) by reacting a phenylacetylene XIV

with a trialkyl phosphite XII or

in succession with phosphorus pentachloride and an alcohol, mercaptan oramine (HZ¹ R¹ /HZ² R²) in the presence of a base

{cf., in this context, for example C. E. Griffin, T. D. Mitchell, J.Org. Chem. 30 (1965) 1935; A. Meisters, J. M. Swan, Aust. J. Chem. 18(1965) 155; L. Maier, Synth. Inorg. Met. Org. Chem. 3 (1973) 329; A. A.Petrov, J. Gen. Chem. USSR 41 (1971) 1670}: ##STR55## As regards thedefinition of Ar, see process A.1).

The reaction of XIV with XII is preferably carried out in the absence ofa solvent at from 20° C. to the boiling point of the trialkyl phosphiteXII, in particular at the boiling point of the reaction mixture.

Bases which are suitable in the reaction of the phenylacetylene XIV withPCl₅ and (HZ¹ R¹ /HZ² H²) are, in particular, tertiary amines such aspyridine and triethylamine.

The reaction of XIV with PCl₅ is preferably carried out at from 50 to200° C., the subsequent reaction with (HZ¹ R¹ /HZ² R²), in contrast, atfrom (-100)°C. to the boiling point of the reaction mixture.

Those phenylacetylenes XIV and alcohols, mercaptans and amines (HZ¹ R¹/HZ² R²) which are not already known can be prepared in a manner knownper se.

A.9) by reacting benzylidenetriphenylphosphoranes XV with aperfluoroalkanecarboxylic anhydride and subsequently with a lithiumdialkyl phosphite in a manner known per se {cf. in this context, forexample, Y. Shen, Q. Liao, W. Qiu, J. Chem. Soc., Perkin Trans 1, 695(1990)}: ##STR56## As regards the definition of Ar, see process A.1); Phis the phenyl group.

Those benzylidenetriphenylphosphoranes XV which are not already knowncan be prepared in a manner known per se.

A.10) by alkylating a phosphonic acid derivative XVI in a manner knownper se using a 3-pyridylbenzyl halide XVII in the presence of a strongbase {cf. in this context, for example, G. M. Blackburn, M. J. Parratt,J. Chem. Soc., Perkin Trans 1, 1425 (1986); G. M. Kosolapoff, J. S.Powell, J. Am. Chem. Soc. 72 (1950) 4198; R. M. Keenan et al., J. Med.Chem. 35 (1992) 3858; H. Ahlbrecht, W. Farnung, Synthesis, 336 (1977);E. D'Incan, J. Seyden-Penne, Synthesis, 516 (1975); S. Hanessian, Y. L.Bennani, D. Delorme, Tetrahedron Lett. 31 (1990) 6461}: ##STR57## Asregards the definition of Ar, see process A.1); R^(f) is hydrogen,cyano, halogen, C₁ -C₄ -alkyl, (C₁ -C₄ -alkoxy)carbonyl or di(C₁ -C₄-alkyl)amino.

Examples of suitable strong bases are sodium hydroxide, butyllithium andlithium diisopropylamide.

The process is normally carried out in an inert organic solvent,preferably in an aromatic hydrocarbon such as toluene or a cyclic ethersuch as tetrahydrofuran.

In general, the process is carried out at from (-100)°C. to the boilingpoint of the reaction mixture, preferably from (-78)°C. to +25° C.

Those phosphonic acid derivatives XVI and those benzyl halides XVIIwhich are not already known can be prepared in a manner known per se.

A.11) by reacting aldehydes XVIIIa/XVIIIb with dialkyl phosphites XIII,if desired in the presence of ammonia or a primary or secondary amine{cf. in this context, for example, M. E. Chalmers, G. M. Kosolapoff, J.Am. Chem. Soc. 75 (1953) 5278; C. Li, C. Yuan, Tetrahedron Lett. 34(1993) 1515}: ##STR58## As regards the definition of Ar, see processA.1); X' is unsubstituted or substituted --CH₂ --, --CH₂ CH₂ --, --OCH₂-- or --SCH₂ --, substituents which are possible being the same as inthe corresponding meanings of X.

Examples of suitable solvents are water, the lower alcohols such asmethanol, ethers such as tetrahydrofuran and diethyl ether, and alsopyridine.

In general, the process is carried out at from (-100)°C. to the boilingpoint of the reaction mixture, preferably from 20 to 50° C.

Those aldehydes XVIIIa/XVIIIb which are not already known can beprepared in a manner known per se.

A.12) by reacting alkyl halides XVII or XIX with trialkyl phosphites XIIin a manner known per se by the method of Arbuzov {see in this context,for example, A. Y. Garner, E. C. Chapin, P. M. Scanlon, J. Org. Chem. 24(1959) 532; A. G. Schultz, J. J. Napier, R. Ravichandran, J. Org. Chem.48 (1983) 3408; Y. Vo-Quang, D. Carniato, L. Vo-Quang, F. Le Goffic, J.Chem. Soc., Chem. Commun., 1505 (1983)}: ##STR59## As regards thedefinition of Ar, see process A.1); X" is, in this context, --OCH₂ --,--SCH₂ -- or --Q--CH₂ -- where Q=unsubstituted or substituted methylene,1,2-ethanediyl, oxymethylene, thiamethylene, methyleneoxy ormethylenethia.

The reaction is preferably carried out in the absence of a solvent, atfrom 0° C. to the boiling point of the trialkyl phosphite XII,preferably from 20 to 150° C.

Those alkyl halides XIX which are not already known can be prepared in amanner known per se.

A.13) by nucleophilic substitution reaction on phosphonic acidderivatives XXI in the presence of a base {cf. in this context, forexample, J. L. Kelley, J. A. Linn, E. W. McLean, J. V. Tuttle, J. Med.Chem. 36 (1993) 3455}: ##STR60## As regards the definition of Ar, seeprocess A.1); L is halogen or a customary leaving group such asmethylsulfonyloxy or 4-tolylsulfonyloxy.

The process is normally carried out in an inert organic solvent,preferably in pyridine, a ketone such as acetone, or in an ether such astetrahydrofuran.

Examples of suitable bases are butyllithium and alkali metal hydridessuch as sodium hydride or alkali metal carbonates such as potassiumcarbonate.

In general, the process is carried out at from (-100)°C. to the boilingpoint of the reaction mixture, preferably from 20 to 50° C.

A further possibility of synthesizing compounds I by means of anucleophilic substitution reaction is to react 3-pyridylbenzyl halidesXVII with phosphonic acid derivatives XXII in a manner known per se inthe presence of a base {see in this context, in addition to theabovementioned references, also S. Jarosz, E. Koslowska, Z. Ciunik, Pol.J. Chem. 68 (1994) 2209}: ##STR61## As regards Ar, solvent, base andreaction temperature, reference may be made to the above information onthe reaction of XX with XXI.

Those phenols XXa and thiophenols XXb, those phosphonic acid derivativesXXI, those benzyl halides XVII and those phosphonic acid derivativesXXII which are not already known can be prepared in a manner known perse.

A.14) by reacting a phenol XXa with a halomethyl thioether XXIII in thepresence of a base, halogenolytic cleavage of the resulting alkylthioalkyl ether XXIV, followed by an Arbuzov reaction: ##STR62## Asregards the definition of Ar, see process A.1); R^(g), R^(h)independently of one another are C₁ -C₄ -alkyl radicals (XXIIIa=XXIIIwhere R^(g) =H and R^(h) =CH₃ ; XXIVa=XXIV where R^(g) =H und R^(h)=CH₃).

As regards the procedure of the nucleophilic substitution reactionXXA+XXIII, reference may be made to the information given in SectionA.13).

The subsequent cleavage of the reaction product XXIV is carried out witha halogen, preferably with chlorine or bromine, at between the meltingpoint and the boiling point of the reaction mixture, preferably at0-100° C. As a rule, the reaction is carried out in an inert organicsolvent, e.g. a hydrocarbon such as n-hexane, a halogenated hydrocarbonsuch as dichloromethane or an ether such as tetrahydrofuran.

Finally, the halomethyl ether XXV is subjected to an Arbuzov reactionwith a trialkyl phosphite XII. As regards the procedure of thisreaction, reference may be made to the information given in SectionA.12).

A.15) by reacting an aldehyde VIa with a trichloromethanephosphonic acidderivative XXVI in the presence of an alkyllithium compound XXVII:##STR63## As regards the definition of Ar, see process A.1).

Normally, the phosphonic acid derivative XXVI is first reacted with thealkyllithium compound XXVII at between the melting point and the boilingpoint of the reaction mixture, preferably at from (-80) to (-50)°C.Normally, the reaction is carried out in an inert organicsolvent/diluent, e.g. a hydrocarbon such as n-hexane or an ether such astetrahydrofuran.

The reaction product is reacted with the aldehyde VIa, preferablywithout working up, during which process the reaction temperature ispreferably raised to approximately 20° C.

A.16) by diazotizating of pyridylanilines II, reacting the resultingdiazonium salts with phosphous trichloride and reacting the reactionproducts with nucleophiles H--OR¹ or H--OR² {see, for example, E.Klumpp, G. Eifert, P. Born, J. Szulagyi, Chem. Ber. 122, (1989), 2021;G. O. Doak et al., J. Am. Chem. Soc. 75, (1953), p. 683, 1379, 4903 and4905}: ##STR64## As regards the diazotization, reference may be made tothe information given in section A.1).

The diazonium salt is preferably isolated prior to the reaction usingphosphorus trichloride, for example as the halide, tetrafluoroborate orhexafluorophosphate. The reaction itself is generally carried out in aninert organic solvent, e.g. a hydrocarbon such as n-hexane and toluene,a halogenated hydrocarbon such as dichloromethane, an ether such astetrahydrofuran, or an aprotic solvent such as acetonitrile,dimethylformamide and dimethyl sulfoxide.

In general, the process is carried out between the melting point and theboiling point of the reaction mixture, preferably at from 0 to 100° C.

The subsequent conversion into I is preferably carried out using wateras the nucleophile.

A.17) by reacting an aryl halide/triflate of the formula IV with adialkyl phosphite XIII in the presence of a base and of a transitionmetal catalyst {see, for example, A. Castelnuovo, J. Calabrese, J. Am.Chem. Soc. 112 (1990), 4324; T. Hirao et al., Bull. Chem. Soc. Jpn. 55(1982), 909}: ##STR65## Examples of suitable bases are amines such astriethylamine.

A suitable catalyst is preferably a palladium compound, for exampletetrakis(triphenylphosphine)palladium. Apart from this, reference may bemade to the information given in section A.2).

B) Derivatization of substituted 2-phenylpyridines of the formula I:

B.1) Hydrogenation of substituted 2-phenylpyridines I where X is1,2-ethenediyl or a halogen-substituted methylene, 1,2-ethanediyl or1,3-propanediyl bridge {cf., for example, C. N. Robinson, P. K. Li. J.F. Addison, J. Org. Chem. 37 (1972) 2939; G. T. Lowen, M. R. Almond, J.Org. Chem. 59 (1994) 4548}: ##STR66## As regards the definition of Ar,see process A.1).

The hydrogenation is carried out either with hydrogen in the presence ofa catalyst conventionally used for this purpose, such as palladium orplatinum on active charcoal or Raney nickel, at from 0 to 150° C. and ahydrogen pressure of approx. 1 to 200 bar, or with a metal hydride suchas sodium borohydride and lithium aluminum hydride at from 0° C. to theboiling point of the reaction mixture.

Examples of solvents which are suitable for the hydrogenation withhydrogen are water, the lower alcohols such as methanol and ethanol,ethers such as diethyl ether and tetrahydrofuran or esters such as ethylacetate.

When reacting the starting compound with a metal hydride, the process ispreferably carried out in an inert organic solvent, in particular anether such as diethyl ether and tetrahydrofuran.

B.2) Hydrolysis of substituted 2-phenylpyridines I, conversion of theprocess products into phosphonyl halides, and reaction of the latterwith nucleophiles: ##STR67##

As regards the definition of Ar, see process A.1).

In this process, the substituted 2-phenylpyridines I are first cleavedhydrolytically (acidic or alkaline) or, if R¹ and/or R² is a benzyl orallyl radical, also hydrogenolytically, to give phosphonic acids andphosphonic monesters I. If desired, the cleavage can also be carried outby means of a reaction with a tri(C₁ -C₄ -alkyl)silyl halide such aschlorotrimethylsilane, iodotrimethylsilane or a mixture ofchlorotrimethylsilane and alkali metal iodine.

The cleavage products can then be converted into the correspondingphosphonyl monochlorides or phosphonyl dichlorides XXVIIIa and XXIXa byreaction with a halogenating agent such as oxalyl chloride, thionylchloride and phosphorus pentachloride.

If desired, the phosphonyl dichlorides XXVIIIa can be thionated in amanner known per se using a thionating agent such as phosphorus(V)sulfide and2,4-bis(4-methoxyphenyl)-1,3,2,4-dithiadiphosphetane-2,4-dithione("Lawesson Reagent") to give thionophosphonyl dichlorides XXVIIIb. Asregards useful solvents, temperature and ratios, reference may be madeto the information given in DE-A 19 504 188 under process D).

Finally, further substituted 2-phenylpyridines I are accessible byreacting XXVIII and XXIX with nucleophiles HZ¹ R¹ or HZ² R².

The chlorophosphonates XXIXa can be converted into the thionophosphonicmonoesters XXIXb for example by conversion with sodium hydrogen sulfide.

As regards the procedure of the reaction and the ratios of thereactants, reference may be made, for example, to Houben-Weyl, Methodender Organischen Chemie [Methods in Organic Chemistry], Georg ThiemeVerlag, Stuttgart, Vol. 12/1, 4th, Edition 1963, pp. 387 et seq., 407 etseq. and 557 et seq.; Vol. E2 1982, pp. 300 et seq. and 419 et seq.

B.3) Elimination of hydrogen halide from compounds I where X═--CH₂--CH(halogen)-- or --CH═C(halogen)--: ##STR68##

The process is normally carried out in water or in an inert organicsolvent, e.g. an alcohol such as ethanol, an ether such as diethylether, tetrahydrofuran and dioxane, or an aprotic solvent such asacetonitrile, dimethylformamide and dimethyl sulfoxide.

Examples of suitable bases are alkali metal hydroxides, alkali metalcarbonates, alkali metal hydrides, alkyl-lithium compounds such asbutyllithium, or organic amines such as triethylamine,1,4-diazabicyclo[2.2.2.]octane (DABCO) and1,8-diazabicyclo[5.4.0.]undec-7-ene (DBU).

In general, the reaction is carried out at from (-100)°C. to the boilingpoint of the reaction mixture, preferably at from 20° to 100° C.

C) Oxidation of substituted phenylpyridines of the formula I where n iszero and the substituent --X--P(═Y) (Z¹ R¹)(Z² R²) does not containsulfur, in a manner known per se {cf., for example, A. Albini & S.Pietra, heterocyclic N-oxides, CRC-Press Inc., Boco Raton, USA 1991; H.S. Mosher et al., Org. Synth. Coll. Vol. IV 1963, page 828; E. C. Tayloret al., Org. Synth. Coll. Vol. IV 1963, page 704; T. W. Bell et al.,Org. Synth. 69 (1990), page 226}: ##STR69## Amongst the oxidantsconventionally used for oxidizing the pyridine ring, reference may bemade way of example to peracetic acid, trifluoroperacetic acid,perbenzoic acid, m-chloroperbenzoic acid, monopermaleic acid, magnesiummonoperphthalate, sodium perborate, Oxone® (contains peroxydisulfate),pertungstic acid and hydrogen peroxide.

Examples of suitable solvents are water, sulfuric acid, carboxylic acidssuch as acetic acid and trifluoroacetic acid, and halogenatedhydrocarbons such as dichloromethane and chloroform.

Normally, the reaction mixture is successfully oxidized at from 0° C. toboiling point.

The oxidant is normally employed in at least equimolar amounts based onthe starting compound. In general, an excess of oxidant has proved to beespecially advantageous.

Unless otherwise specified, all processes described hereinabove areexpediently carried out under atmospheric pressure or under the inherentpressure of the reaction mixture in question. The reactants aregenerally employed in a molar ratio of from 0.95:1 to 5:1.

In general, the reaction mixtures are worked up by methods known per se,for example by diluting the reaction solution with water followed byisolation of the product by means of filtration, crystallization orsolvent extraction, or by removing the solvent, partitioning the residuein a mixture of water and a suitable organic solvent and working up theorganic phase to give the product.

The substituted 2-phenylpyridines I can be obtained upon preparation inthe form of isomer mixtures which, however, if desired, can be separatedinto the pure isomers by the methods conventionally used for such cases,such as crystallization or chromatography, also on an optically activeabsorbate. Pure optically active isomers can be prepared advantageouslyfrom suitably optically active starting materials.

Agriculturally useful salts of the compounds I can be formed by reactionwith a base of the corresponding cation, preferably an alkali metalhydroxide or alkali metal hydride, or by reaction with an acid of thecorresponding anion, preferably of hydrochloric acid, hydrobromic acid,sulfuric acid, phosphoric acid or nitric acid.

Salts of I whose metal ion is not an alkali metal ion can also beprepared in the customary manner by double decomposition of thecorresponding alkali metal salt, also ammonium, phosphonium, sulfoniumand sulfoxonium salts by means of ammonia, phosphonium hydroxide,sulfonium hydroxide or sulfoxonium hydroxide.

The compounds I and their agriculturally useful salts are suitable asherbicides, both in the form of isomer mixtures and in the form of thepure isomers. The herbicidal compositions comprising I effect very goodcontrol of vegetation on non-crop areas, especially at high rates ofapplication. In crops such as wheat, rice, maize, soybeans and cottonthey act against broadleaved weeds and grass weeds without damaging thecrop plants substantially. This effect is observed especially at lowrates of application.

Depending on the application method in question, the compounds I, orherbicidal compositions comprising them, can additionally be employed ina further number of crop plants for eliminating undersirable plants.Examples of suitable crops are the following: Allium cepa, Ananascomosus, Arachis hypogaea, Asparagus officinalis, Beta vulgaris spec.altissima, Beta vulgaris spec. rapa, Brassica napus var. napus, Brassicanapus var napobrassica, Brassica rapa var. silvestris, Camelliasinensis, Carthamus tinctorius, Carya illinoinensis, Citrus limon,Citrus sinensis, Coffea arabica (Coffea canephora, Coffea liberica),Cucumis sativus, Cynodon dactylon, Daucus carota, Elaeis guineensis,Fragaria vesca, Glycine max, Gossypium hirsutum, (Gossypium arboreum,Gossypium herbaceum, Gossypium vitifolium), Helianthus annuus, Heveabrasiliensis, Hordeum vulgare, Humulus lupulus, Ipomoea batatas, Juglansregia, Lens culinaris, Linum usitatissimum, Lycopersicon lycopersicum,Malus spec., Manihot esculenta, Medicago sativa, Musa spec., Nicotianatabacum (N. rustica), Olea europaea, Oryza sativa, Phaseolus, lunatus,Phaseolus vulgaris, Picea abies, Pinus spec., Pisum sativum, Prunusavium, Prunus persica, Pyrus communis, Ribes sylvestre, Ricinuscommunis, Saccharum officinarum, Secale cereale, Solanum tuberosum,Sorghum bicolor (S. vulgare), Theobroma cacao, Trifolium pratense,Triticum aestivum, Triticum durum, Vicia faba, Vitis vinifera and Zeamays.

Moreover, the compounds I can also be used in crops which tolerate theaction of herbicides due to breeding including genetic engineeringmethods.

Furthermore, the substituted 2-phenylpyridines I are also suitable forthe desiccation and/or defoliation of plants.

As desiccants, they are especially suitable for desiccating the aerialparts of crop plants such as potatoes, oilseed rape, sunflowers andsoybeans. This allows completely mechanical harvesting of theseimportant crop plants.

Also of economic interest is facilitated harvesting, which is madepossible by concentrating, over a period of time, dehiscence, or reducedadhesion to the tree, in the case of citrus fruit, olives or otherspecies and varieties of pomaceous fruit, stone fruit and nuts. The samemechanism, i.e. promotion of the formation of abscission tissue betweenfruit or leaf and shoot of the plants is also essential for readilycontrollable defoliation of useful plants, in particular cotton.

Moreover, a shortened period of time within which the individual cottonplants ripen results in an increased fiber quality after harvesting.

The compounds I, or the compositions comprising them, can be employed,for example, in the form of directly sprayable aqueous solutions,powders, suspensions, also highly-concentrated aqueous, oily or othersuspensions or dispersions, emulsions, oil dispersions, pastes, dusts,materials for spreading or granules, by means of spraying, atomizing,dusting, spreading or pouring. The use forms depend on the intendedpurposes; in any case, they should guarantee the finest possibledistribution of the active ingredients according to the invention.

Suitable inert auxiliaries are essentially: mineral oil fractions ofmedium to high boiling point such as kerosene and diesel oil,furthermore coal tar oils and oils of vegetable or animal origin,aliphatic, cyclic and aromatic hydrocarbons, e.g. paraffins,tetrahydronaphthalene, alkylated naphthalenes and their derivatives,alkylated benzenes and their derivatives, alcohols such as methanol,ethanol, propanol, butanol and cyclohexanol, ketones such ascyclohexanone, strongly polar solvents, e.g. amines such asN-methylpyrrolidione and water.

Aqueous use forms can be prepared from emulsion concentrates,suspensions, pastes, wettable powders or water-dispersible granules byadding water. To prepare emulsions, pastes or oil dispersions, thesubstances, as such or dissolved in an oil or solvent, can behomogenized in water by means of wetting agent, tackifier, dispersant oremulsifier. However, it is also possible to prepare concentratescomposed of active substance, wetting agent, tackifier, dispersant oremulsifier and, if appropriate, solvent or oil, and these concentratesare suitable for dilution with water.

Suitable surfactants are the alkali metal, alkaline earth metal andammonium salts of aromatic sulfonic acids, e.g. ligno-, phenol-,naphthalene- and dibutylnaphthalenesulfonic acid, and of fatty acids, ofalkyl- and alkylaryl sulfonates, of alkyl sulfates, lauryl ethersulfates and fatty alcohol sulfates, and salts of sulfated hexa-, hepta-and octadecanols, and of fatty alcohol glycol ether, condensates ofsulfonated naphthalene and its derivatives with formaldehyde,condensates of naphthalene, or of the naphthalenesulfonic acids, withphenol and formaldehyde, polyoxyethylene octylphenyl ether, ethoxylatedisooctyl-, octyl- or nonylphenol, alkylphenyl and tributylphenylpolyglycol ether, alkylaryl polyether alcohols, isotridecyl alcohol,fatty alcohol/ethylene oxide condensates, ethoxylated castor oil,polyoxyethylene alkyl ethers or polyoxypropylene alkyl ethers, laurylalcohol polyglycol ether acetate, sorbitol esters, lignin-sulfite withliquors or methylcellulose.

Powders, materials for spreading and dusts can be prepared by mixing orconcommitantly grinding the active substances with a solid carrier.

Granules, e.g. coated granules, impregnated granules and homogeneousgranules, can be prepared by binding the active ingredients to solidcarriers. Solid carriers are mineral earths such as silicas, silicagels, silicates, talc, kaolin, limestone, lime, chalk, bole, loess,clay, dolomite, diatomaceous earth, calcium sulfate, magnesium sulfate,magnesium oxide, ground synthetic material, fertilizers such as ammoniumsulfate, ammonium phosphate, ammonium nitrate, ureas and products ofvegetable origin such as cereal meal, tree bark meal, wood meal andnutshell meal, cellulose powders or other solid carriers.

The concentrations of the active ingredients I in the ready-to-useproducts can be varied within wide ranges. In general, the formulationscomprise approximately from 0.001 to 98% by weight, preferably 0.01 to95% by weight, of at least one active ingredient. The active ingredientsare employed in a purity of from 90% to 100%, preferably 95% to 100%(according to NMR spectrum).

The formulation examples below illustrate the preparation of suchproducts:

I. 20 parts by weight of the compound No. Iaα.3 are dissolved in amixture composed of 80 parts by weight of alkylated benzene, 10 parts byweight of the adduct of 8 to 10 mol of ethylene oxide and 1 mol of oleicacid N-monoethanolamide, 5 parts by weight of calciumdodecylbenzenesulfonate and 5 parts by weight of the adduct of 40 mol ofethylene oxide and 1 mol of castor oil. Pouring the solution into100,000 parts by weight of water and finely distributing it whereingives an aqueous dispersion which comprises 0.02% by weight of theactive ingredient.

II. 20 parts by weight of the compound No. Icα.3 are dissolved in amixture composed of 40 parts by weight of cyclohexanone, 30 parts byweight of isobutanol, 20 parts by weight of the adduct of 7 mol ofethylene oxide and 1 mol of isooctylphenol and 10 parts by weight of theadduct of 40 mol of ethylene oxide and 1 mol of castor oil. Pouring thesolution into 100,000 parts by weight of water and finely distributingit therein gives an aqueous dispersion which comprises 0.02% by weightof the active ingredient.

III. 20 parts by weight of the active ingredients No. Idα.2 aredissolved in a mixture composed of 25 parts by weight of cyclohexanone,65 parts by weight of a mineral oil fraction of boiling point 210° to280° C. and 10 parts by weight of the adduct of 40 mol of ethylene oxideand 1 mol of castor oil. Pouring the solution into 100,000 parts byweight of water and finely distributing it therein gives an aqueousdispersion which comprises 0.02% by weight of the active ingredient.

IV. 20 parts by weight of the active ingredient No. Ifα.3 are mixedthoroughly with 3 parts by weight of sodiumdiisobutylnaphthalene-α-sulfonate, 17 parts by weight of the sodium saltof a lignosulfonic acid from a sulfite waste liquor and 60 parts byweight of pulverulent silica gel and the mixture is ground in a hammermill. Finely distributing the mixture in 20,000 parts by weight of watergives a spray mixture which comprises 0.1% by weight of the activeingredient.

V. 3 parts by weight of the active ingredient No. Icγ.2 are mixed with97 parts by weight of finely divided kaolin. This gives a dust whichcomprises 3% by weight of the active ingredient.

VI. 20 parts by weight of the active ingredient No. Icγ.3 are mixedintimately with 2 parts by weight of calcium dodecylbenzenesulfonate, 8parts by eight of fatty alcohol polyglycol ether, 2 parts by weight ofthe sodium salt of a phenol/urea/formaldehyde condensate and 68 parts byweight of a paraffinic mineral oil. This gives a stable oily dispersion.

VII. 1 part by weight of the compound No. Inα.3 is dissolved in amixture composed of 70 parts by weight of cyclohexanone, 20 parts byweight of ethoxylated isooctylphenol and 10 parts by weight ofethoxylated castor oil. The mixture can subsequently be diluted withwater to give the desired concentration of active ingredient. This givesa stable emulsion concentrate.

VIII. 1 part by weight of the compound No. Iiα.38 is dissolved in amixture composed of 80 parts by weight of cyclohexanone and 20 parts byweight of Wettol® EM 31 (=non-ionic emulsifier based on ethoxylatedcastor oil). The mixture can subsequently be diluted with water to givethe desired concentration of active ingredient. This gives a stableemulsion concentrate.

The active ingredients I, or the herbicidal compositions comprisingthem, can be applied pre- or post-emergence. If the active ingredientsare less well tolerated by certain crop plants, application techniquesmay be used in which the herbicidal compositions are sprayed, with theaid of the spray apparatus, in such a way that they come into as littlecontact, if any, with the leaves of the sensitive crop plants whilereaching the leaves of undesirable plants which grow underneath, or thebare soil (post-directed, lay-by).

Depending on the intended aim of the control measures, the season, thetarget plants and the growth stage, the application rates of activeingredient I are from 0.001 to 3.0, preferably 0.01 to 1.0 kg/ha activesubstance (a.s.).

To widen the spectrum of action and to achieve synergistic effects, thesubstituted 2-phenylpyridines I can be mixed and applied jointly with alarge number of representatives of other groups of herbicidally orgrowth-regulatory active ingredients. Suitable components in mixturesare, for example, 1,2,4-thiadiazoles, 1,3,4-thiadiazoles, amides,aminophosphoric acid and its derivatives, aminotriazoles, anilides,aryloxy-/hetaryloxyalkanic acids and their derivatives, benzoic acid andits derivatives, benzothiadiazinones,2-(hetaroyl/aroyl)-1,3-cyclohexanediones, hetaryl aryl ketones,benzylisoxazolidinones, meta-CF₃ -phenylderivatives, carbamates,quinolinecarboxylic acid and its derivatives, chloracetanilides,cyclohexane-1,3-dione derivatives, diazines, dichloropropionic acid andits derivatives, dihydrobenzofuranes, dihydrofuran-3-ones,dinitroanilines, dinitrophenoles, diphenyl ethers, dipyridyls,halocarboxylic acids and their derivatives, ureas, 3-phenyluracils,imidazoles, imidazolinones, N-phenyl-3,4,5,6-tetrahydrophthalimides,oxadiazoles, oxiranes, phenols, aryloxy- and hetaryloxyphenoxypropionicesters, phenylacetic acid and its derivatives, 2-phenylpropionic acidand its derivatives, pyrazoles, phenylpyrazoles, pyridazines,pyridinecarboxylic acid and its derivatives, pyrimidyl ethers,sulfonamides, sulfonylureas, triazines, triazinones, triazolinones,triazole carboxamides and uracils.

Moreover, it may be advantageous to apply the compounds I, alone or incombination with other herbicides, in the form of a mixture withadditional other crop protection agents, for example with pesticides oragents for controlling phytopathogenic fungi or bacteria. Also ofinterest is the miscibility with mineral salt solutions which areemployed for treating nutritional and trace element deficiencies.Non-phytotoxic oils and oil concentrates can also be added.

PREPARATION EXAMPLES Example 1

Diethyl1-chloro-2-(2-chloro-5-(3-chloro-5-trifluoromethylpyrid-2-yl)-4-fluorophenyl)ethylphosphonate(No. Icγ.3)

3 g (9 mmol) of2-chloro-5-(3-chloro-5-trifluoromethylpyrid-2-yl)-4-fluoroaniline wereadded to a solution of 30.3 g (0.19 mol) of diethyl vinylphosphonate,1.4 g of copper(II) chloride (10 mmol) and 1 g (10 mmol) of tert-butylnitrite in 150 ml of acetonitrile. After 3 hours, 200 ml of methyltert-butyl ether were added to the reaction mixture. The organic phasewas subsequently washed twice with water, then dried over magnesiumsulfate and finally concentrated. The crude product was purified bycolumn chromatography (eluent: hexane/ethyl acetate=4:1). Yield: 1.6 g.

Example 2

Diethyl1-chloro-2-(2-chloro-5-(3-chloro-5-trifluoromethylpyrid-2-yl)-4-fluorophenyl)vinylphosphonate(No. Iiγ.3)

3 ml of butyllithium solution (1.5M in hexane; 4.5 mmol) were added to asolution, cooled to (-70)°C., of 2.3 g (9 mmol) of diethyltrichloromethanephosphonate in 30 ml of tetrahydrofuran in such a waythat the temperature did not rise above (-65)°C. Stirring of the mixturewas then continued for 1 hour at (-65) to (-70)°C., whereupon a solutionof 1 g (3 mmol) of2-chloro-5-(3-chloro-5-trifluoromethylpyrid-2-yl)-4-fluorobenzaldehydein 20 ml of tetrahydrofuran was slowly added dropwise. After the mixturehad been stirred for a further 30 minutes, the cooling bath was removedand the mixture was allowed to come to room temperature. The reactionsolution was subsequently washed with saturated aqueous sodium chloridesolution, then dried over magnesium sulfate and finally concentrated.The crude product was purified by column chromatography on silica gel(eluent: hexane/ethyl acetate=4:1). Yield: 0.8 g.

Example 3

Dimethyl1-bromo-2-[2-chloro-5-(3-chloro-5-trifluoromethylpyrid-2-yl)phenyl]ethylphosphonate(No. Idα.2)

By following a method similar to the one described for Example 1 andusing 32.6 g (0.24 mol) of dimethyl vinylphosphonate, 3.13 g (14 mmol)of copper(II) bromide, 1.33 g (13 mmol) of tert-butyl nitrite and 3.6 g(12 mmol) of 2-chloro-5-(3-chloro-5-trifluoromethylpyrid-2-yl)aniline,1.2 g of the desired product of value were obtained.

Example 4

Diethyl2-chloro-5-(3-chloro-5-trifluoromethylpyrid-2-yl)benzyloxymethylphosphonate(No. Inα.3)

To a solution of 0.66 g (3.9 mmol) of diethyl hydroxymethylphosphonatein 30 ml of tetrahydrofuran there were added 0.1 g (3.6 mmol) of sodiumhydride and, after the mixture had been stirred for 15 minutes, 1 g (2.6mmol) of 2-chloro-5-(3-chloro-5-trifluoromethylpyrid-2-yl)benzylbromide. The mixture was subsequently stirred for 16 hours. The reactionmixture was then concentrated. The crude product obtained was purifiedby means of silica gel chromatography (eluent: hexane/ethylacetate=1:1). Yield: 0.8 g.

Example 5

Diethyl2-chloro-5-(3-chloro-5-trifluoromethylpyrid-2-yl)-4-fluorophenoxymethylphosphonate(No. Ioγ.3)

0.14 g (0.78 mmol) of bromine was added to a solution of 0.3 g (0.78mmol) of3-chloro-2-[4-chloro-2-fluoro-5-(methylthiomethoxy)phenyl]-5-trifluoromethylpyridin 10 ml of tetrachloromethane. After the mixture had been stirred for 2hours, it was concentrated. The residue was treated with 20 ml oftriethyl phosphite. Stirring was subsequently continued for 16 hours,whereupon excess phosphite was removed under a high vacuum. Yield: 0.2g.

Precursor 5.1

3-Chloro-2-[4-chloro-2-fluoro-5-(methylthiomethoxy)phenyl]-5-trifluoromethylpyridine

0.1 g (4.4 mmol) of sodium hydride was added to a solution of 1.3 g (4mmol) of2-chloro-5-(3-chloro-5-trifluoromethylpyrid-2-yl)-4-fluorophenol in 50ml of dimethylformamide. After the mixture has been stirred for 1 hour,it was treated with 0.5 g (5.2 mmol) of methylthiomethyl chloride. Then,the mixture was stirred for another hour. For working-up, the reactionmixture was treated with 50 ml of water. The product was then extractedwith 100 ml of methyl tert-butyl ether. The organic phase was dried overmagnesium sulfate and finally concentrated. Yield: 0.3 g.

¹ H NMR (270 MHz, in CDCl₃): δ [ppm]=2.31 (s, 3H), 5.24 (s, 2H), 7.12(d, 1H), 7.30 (d, 1H), 8.08 (s, 1H), 8.88 (s, 1H).

Example 6

Diethyl2-chloro-5-(3-chloro-5-trifluoromethylpyrid-2-yl)benzylphosphonate (No.Iaα.3)

A solution of 1 g (2.6 mmol) of2-chloro-5-(3-chloro-5-trifluoromethylpyrid-2-yl)benzyl bromide in 10 mlof triethyl phosphite was heated for 12 hours at 80° to 90° C.,whereupon excess triethyl phosphite was distilled off under a highvacuum. Yield: 1.1 g.

Example 7

1-Chloro-2-[2-chloro-5-(3-chloro-5-trifluoromethylpyrid-2-yl)-4-fluorophenyl]ethylphosphonicacid (No. Icγ.1)

0.7 g (4.2 mmol) of potassium iodide and 0.46 g (4.2 mmol) ofchlorotrimethylsilane were added to a solution of 0.7 g (1.4 mol) ofdiethyl1-chloro-2-[2-chloro-5-(3-chloro-5-trifluoromethylpyrid-2-yl)-4-fluorophenyl]ethylphosphonatein 20 ml of acetonitrile. The mixture was then heated for 4 hours at 50°to 60° C. whereupon it was concentrated. 20 ml of water and 50 ml ofethyl acetate were added to the residue. The organic phase was separatedoff, dried over magnesium sulfate and finally concentrated. Yield:quantitative.

Example 8

Diethyl1-cyano-2-[2-chloro-5-(3-chloro-5-trifluoromethylpyrid-2-yl)phenyl]ethylphosphonate(No. Ifα.3)

2.27 ml (3.6 mmol) of 1.6M butyllithium solution in n-hexane were addedto a solution, cooled to (-78)°C., of 0.69 g (3.89 mmol) of diethylcyanomethylphosphonate in 50 ml of tetrahydrofuran. After the mixturehad been stirred for 1 hour, it was treated with 1 g (2.6 mmol) of2-chloro-5-(3-chloro-5-trifluoromethylpyrid-2-yl)benzyl bromide,dissolved in 10 ml of tetrahydrofuran. The mixture was then stirred foranother 16 hours at approximately 20° C. It was then concentrated, andthe residue which remained was treated with 50 ml of ethyl acetate. Theproduct-containing organic phase was separated off, washed with waterand saturated aqueous sodium chloride solution, dried over magnesiumsulfate and finally concentrated. The crude product was purified bymeans of silica gel chromatography (eluent: hexane/ethyl acetate=4:1).Yield: 0.6 g.

Example 9

Diethyl1-chloro-2-[2-chloro-5-(3-chloro-5-trifluoromethylpyrid-2-yl)phenyl]vinylphosphonate(No. Iiα.3)

By following a method similar to Example 2 and using 33.7 g (0.13 mol)of diethyl trichloromethanephosphante, 41 ml of a butyllithium solution(1.6M in n-hexane; 63 mmol n-butyllithium) and 8.3 g (26 mmol) of2-chloro-5-(3-chloro-5-trifluoromethylpyrid-2-yl)-benzaldehyde, 10 g ofthe desired product of value were obtained.

Example 10

1-Chloro-2-[2-chloro-5-(3-chloro-5-trifluoromethylpyrid-2yl)-phenyl]vinylphosphonicacid (No. Iiα.1)

By following a method similar to the one described for Example 7 andusing 4 g (8.1 mmol) of diethyl1-chloro-2-[2-chloro-5-(3-chloro-5-trifluoromethylpyrid-2-yl)phenyl]vinylphosphonate,4 g (24 mmol) of potassium iodide and 2.7 g (24 mmol) ofchlorotrimethylsilane, 3 g of the desired product of value wereobtained.

Example 11

Diallyl 1-chloro-2-[2-chloro-5-(3-chloro-5-trifluoromethylpyrid-2-yl)phenyl]vinylphosphonate (No. Iiα.32)

0.9 g (7 mmol) of oxalyl chloride was added to a solution of 1 g (2.3mmol) of1-chloro-2-[2-chloro-5-(3-chloro-5-trifluoromethylpyrid-2-yl)phenyl]vinylphosphonicacid in 15 ml of 1,2-dichloroethane. Then, the reaction mixture washeated briefly to reflux temperature and subsequently concentrated. Theresulting acid chloride was dissolved in 50 ml of dichloromethane. After0.55 g (6.3 mmol) of pyridine and 0.4 g (6.3 mmol) of allyl alcohol hadbeen added, the mixture was stirred for a further 16 hours. The mixturewas then treated with water. The organic phase was subsequentlyseparated off, dried over magnesium sulfate and concentrated. The crudeproduct was purified by means of silica gel chromatography (eluent:hexane/ethyl acetate=4:1). Yield: 0.2 g.

In addition to those described above, a further number of substituted2-phenylpyridines which were, or can be, prepared by similar methods arelisted in Table 2 below:

                                      TABLE 2                                     __________________________________________________________________________     ##STR70##                                                                                                 M.p./.sup.1 H NMR                                No. R.sup.4                                                                         --X--    --P(═Y)(Z.sup.1 R.sup.1 (Z.sup.2 R.sup.2)                                               (δ in [ppm]), MS [m/z]                     __________________________________________________________________________    Iaα. 3                                                                      H --CH.sub.2 --                                                                          --P(═O)(OC.sub.2 H.sub.5).sub.2                                                         1.27(t, 6H), 3.44(d, 2H),                                                     4.09(quint., 4H),                                                             7.51(d, 1H), 7.64(dd, 1H),                                                    7.88(d, 1H), 8.03(d, 1H),                                                     8.83(d, 1H)                                      Icα. 2                                                                      H --CH.sub.2 --CH(Cl)--                                                                  --P(═O)(OCH.sub.3).sub.2                                                                426[M--Cl].sup.+                                 Icα. 3                                                                      H --CH.sub.2 --CH(Cl)--                                                                  --P(═O)(OC.sub.2 H.sub.5).sub.2                                                         454[M--Cl].sup.+                                 Idα. 2                                                                      H --CH.sub.2 --CH(Br)--                                                                  --P(═O)(OCH.sub.3).sub.2                                                                504[M--H].sup.+, 470[M--Cl].sup.+                Idα. 3                                                                      H --CH.sub.2 --CH(Br)--                                                                  --P(═O)(OC.sub.2 H.sub.5).sub.2                                                         1.38(t, 6H), 3.22(ddd, 1H),                                                   3.82(ddd, 1H), 4.27(m, 5H),                                                   7.52(d, 1H), 7.68(dd, 1H),                                                    7.75(d, 1H), 8.08(s, 1H),                                                     8.86(s, 1H)                                      Ifα. 3                                                                      H --CH.sub.2 --CH(CN)--                                                                  --P(═O)(OC.sub.2 H.sub.5).sub.2                                                         1.39(t, 3H), 1.43(t, 3H),                                                     3.18(ddd, 1H), 3.42(ddd, 1H),                                                 3.56(ddd, 1H), 4.30(m, 4H),                                                   7.54(d, 1H), 7.73(dd, 1H),                                                    7.83(d, 1H), 8.05(d, 1H),                                                     8.85(d, 1H)                                      Icγ. 1                                                                      F --CH.sub.2 --CH(Cl)--                                                                  --P(═O)(OH).sub.2                                                                       3.12(ddd, 1H),                                                                3.59(brd, 1H),                                                                4.19(brt, 1H), 7.64(d, 1H),                                                   7.68(d, 1H), 8.66(s, 1H),                                                     9.10(s, 1H), 10.95(s, 2H)                        Icγ. 2                                                                      F --CH.sub.2 --CH(Cl)--                                                                  --P(═O)(OCH.sub.3).sub.2                                                                3.14(ddd, 1H),                                                                3.67(ddd, 1H), 3.88(d, 3H),                                                   3.94(d, 3H), 4.26(dt, 1H),                                                    7.29(d, 1H), 7.45(d, 1H),                                                     8.07(s, 1H), 8.86(s, 1H)                         Icγ. 3                                                                      F --CH.sub.2 --CH(Cl)--                                                                  --P(═O)(OC.sub.2 H.sub.5).sub.2                                                         1.39(t, 3H), 1.40(t, 3H),                                                     3.12(dt, 1H), 3.70(ddd, 1H),                                                  4.20-4.33(m, 5H),                                                             7.29(d, 1H), 7.46(d, 1H),                                                     8.08(s, 1H), 8.88(s, 1H)                         Inα. 3                                                                      H --CH.sub.2 --OCH.sub.2 --                                                              --P(═O)(OC.sub.2 H.sub.5).sub.2                                                         1.32(t, 6H), 3.90(d, 2H),                                                     4.19(quint., 4H),                                                             4.83(s, 2H), 7.50(d, 1H),                                                     7.68(dd, 1H), 7.92(d, 1H),                                                    8.07(s, 1H), 8.84(s, 1H)                         Iiα. 1                                                                      H --CH═C(Cl)--                                                                       --P(═O)(OH).sub.2                                                                       resin                                            Iiα. 3                                                                      H --CH═C(Cl)--                                                                       --P(═O)(OC.sub.2 H.sub.5).sub.2                                                         1.42(t, 6H), 4.24(m, 4H),                                                     7.58(d, 1H), 7.77(dd, 1H),                                                    7.96(d, 1H), 8.07(d, 1H),                                                     8.32(d, 1H), 8.86(d, 1H)                         Iiα. 32                                                                     H --CH═C(Cl)--                                                                       --P(═O)(OCH.sub.2 --CH═CH.sub.2).sub.2                                              4.67(m, 4H), 5.29(d, 2H),                                                     5.43(d, 2H), 5.98(m, 2H),                                                     7.58(d, 1H), 7.77(dd, 1H),                                                    7.98(d, 1H), 8.06(d, 1H),                                                     8.31(d, 1H), 8.86 d, 1H)                         Iiα. 36                                                                     H --CH═C(Cl)--                                                                       --P(═O)(OCH.sub.2 --C.tbd.CH).sub.2                                                     2.62(t, 2H), 4.84(dd, 4H),                                                    7.59(d, 1H), 7.78(dd, 1H),                                                    8.01(d, 1H), 8.06(d, 1H),                                                     8.33(d, 1H), 8.86(d, 1H)                         Iiα. 38                                                                     F --CH═C(Cl)--                                                                       --P(═O)(OCH.sub.2 --CO--OCH.sub.3).sub.2                                                3.82(s, 3H), 4.77(dd, 2H),                                                    4.86(dd, 2H), 7.59(d, 1H),                                                    7.78(dd, 1H), 8.06(d, 1H),                                                    8.08(d, 1H), 8.36(d, 1H),                                                     8.86(d, 1H)                                      Iiα. 398                                                                    H --CH═C(Cl)--                                                                       --P(═O)[N(CH.sub.3)--                                                                   1.92(m, 1H), 2.22(m, 1H),                                       --CH.sub.2 --CH.sub.2 --CH.sub.2 --N(CH.sub.3)]                                             2.72(d, 6H), 3.16(m, 2H),                                                     3.39(m, 2H), 7.56(d, 1H),                                                     7.72(dd, 1H), 7.87(d, 1H),                                                    8.06(d, 1H), 8.23(d, 1H),                                                     8.86(d, 1H)                                      Iiγ. 3                                                                      F --CH═C(Cl)--                                                                       --P(═O)(OC.sub.2 H.sub.5).sub.2                                                         1.41(t, 6H),                                                                  4.15-4.30(m, 4H),                                                             7.36(d, 1H), 7.91(d, 1H),                                                     8.09(m, 2H), 8.89(S, 1H)                         Ioγ. 3                                                                      F --OCH.sub.2 --                                                                         --P(═O)(OC.sub.2 H.sub.5).sub.2                                                         1.30(m, 6H),                                                                  4.00-4.30(m, 6H),                                                             7.11(d, 1H), 7.15(dd, 1H),                                                    8.06(s, 1H), 8.83(s, 1H)                         __________________________________________________________________________

Use Examples (herbicidal activity)

The herbicidal action of the substituted 2-phenylpyridines I wasdemonstrated by the following greenhouse experiments:

The culture containers used were plastic flowerpots containing loamysand with approximately 3.0% of humus as substrate. The seeds of thetest plants were sown separately for each species.

For the pre-emergence treatment, the active ingredients, suspended oremulsified in water, were applied directly after sowing by means offinely distributing nozzles. The containers were irrigated gently topromote germination and growth and subsequently covered with translucentplastic hoods until the plants had rooted. This cover caused uniformgermination of the test plants unless this was adversely affected by theactive ingredients.

For the post-emergence treatment, the test plants were grown to a plantheight of from 3 to 15 cm, depending on the plant habit, and only thentreated with the active ingredients which had been suspended oremulsified in water. To this end, the test plants were either sowndirectly and grown in the same containers, or they were first grownseparately as seedlings and transplanted into the test containers a fewdays prior to treatment. The rate of application for the post-emergencetreatment was 15.6, 7.8, 3.9 or 1.9 g/ha a.s. (active substance).

Depending on the species, the plants were kept at from 10°-25° C. and20°-35° C., respectively. The test period extended over 2 to 4 weeks.During this time, the plants were tended, and their response to theindividual treatments was evaluated.

Evaluation was carried out using a scale of from 0 to 100. 100 means noemergence of the plants, or complete destruction of at least the aerialparts, and 0 means no damage or normal course of growth.

The plants used in the greenhouse experiments belonged to the followingspecies:

    ______________________________________                                        Scientific Name   Common Name                                                 ______________________________________                                        Amaranthus retroflexus                                                                          redroot pigweed                                             Chenopodium album lambsquarters (goose foot)                                  Galium aparine    catchweed bedstraw                                          Ipomoea subspecies                                                                              morningglory                                                Polygonum persicaria                                                                            lady's thumb                                                Solanum nigrum    black nightshade                                            ______________________________________                                    

When rates of application of 3.9 and 1.9 g/ha a.s. were appliedpost-emergence, the compound No. Icγ.3 was very effective against theabovementioned plants.

When rates of 15.6 and 7.8 g/ha a.s. were applied, the compound No.Icγ.3 allowed a considerably better control of Amaranthus retroflexus,Galium aparine, Ipomoea subspecies, Polygonum persicaria and Solanumnigrum than the comparison compound A ##STR71## which is known from ACSSymp. Ser. 584, (1995), 90.

Use Examples (desiccant/defoliant activity)

The test plants used were young cotton plants with 4 leaves (withoutcotyledones) which had been grown under greenhouse conditions (relativeatmospheric humidity 50 to 70%; day/night temperature 27°/20° C.).

The young cotton plants were subjected to foliar treatment with aqueouspreparations of the active ingredients (with an addition of 0.15% byweight of the fatty alcohol alkoxylate Plurafac® LF 700¹), based on thespray mixture) until runoff point was reached. The amount of waterapplied was 1000 l/ha (converted). After 13 days, the number of leavesshed and the degree of defoliation in % were determined.

No leaves were shed in the untreated control plants.

We claim:
 1. A 2-phenylpyridine of the formula I ##STR72## where thevariables have the following meanings: X is a chemical bond,1,2-ethynediyl ora methylene, 1,2-ethanediyl or 1,3-propylene bridge,which is unsubstituted or carries a hydroxyl, amino or C₁ -C₄-alkylamino substituent; methyleneoxymethylene, methylenethiamethylene,ethene-1,2-diyl, or oxymethylene, thiamethylene, oxyethylene orthiaethylene, bonded to the phenyl ring via the hetero atom, the lasttwo of these chains being unsubstituted or having hydroxyl, amino or C₁-C₄ -alkylamino attached to the carbon atom adjacent to the phosphorus;and where in each of the last mentioned 10 bridges is unsubstituted orcarries one or two of the following substituents: cyano, carboxyl,halogen, C₁ -C₄ -alkyl, C₁ -C₄ -haloalkyl, C₁ -C₄ -alkoxy, C₁ -C₄-haloalkoxy, (C₁ -C₄ -alkoxy)carbonyl and di-(C₁ -C₄ -alkyl)amino; Y isoxygen or sulfur; Z¹ is oxygen, sulfur or --N(R⁷)--; Z² is oxygen,sulfur or --N(R⁸)--; R¹, R², R⁷ and R⁸ independently of one another arehydrogen, C₁ -C₆ -alkyl, C₁ -C₆ -haloalkyl, hydroxy-C₁ -C₄ -alkyl,cyano-C₁ -C₄ -alkyl, C₁ -C₄ -alkoxy-C₁ -C₄ -alkyl, C₁ -C₄ -haloalkoxy-C₁-C₄ -alkyl, C₃ -C₄ -alkenyloxy-C₁ -C₄ -alkyl, C₃ -C₄ -alkynyloxy-C₁ -C₄-alkyl, C₃ -C₈ -cycloalkoxy-C₁ -C₄ -alkyl, amino-C₁ -C₄ -alkyl, C₁ -C₄-alkylamino-C₁ -C₄ -alkyl, di(C₁ -C₄ -alkyl)amino-C₁ -C₄ -alkyl, C₁ -C₄-alkylthio-C₁ -C₄ -alkyl, C₁ -C₄ -haloalkylthio-C₁ -C₄ -alkyl, C₃ -C₄-alkenylthio-C₁ -C₄ -alkyl, C₃ -C₄ -alkynylthio-C₁ -C₄ -alkyl, C₁ -C₄-alkylsulfinyl-C₁ -C₄ -alkyl, C₁ -C₄ -haloalkylsulfinyl-C₁ -C₄ -alkyl,C₃ -C₄ -alkenylsulfinyl-C₁ -C₄ -alkyl, C₃ -C₄ -alkynyl-sulfinyl-C₁ -C₄-alkyl, C₁ -C₄ -alkylsulfonyl-C₁ -C₄ -alkyl, C₁ -C₄-haloalkylsulfonyl-C₁ -C₄ -alkyl, C₃ -C₄ -alkenylsulfonyl-C₁ -C₄ -alkyl,C₃ -C₄ -alkynylsulfonyl-C₁ -C₄ -alkyl, C₃ -C₆ -alkenyl, C₃ -C₆-haloalkenyl, cyano-C₃ -C₆ -alkenyl, C₃ -C₆ -alkynyl, C₃ -C₆-haloalkynyl, cyano-C₃ -C₆ -alkynyl, hydroxycarbonyl-C₁ -C₄ -alkyl, (C₁-C₄ -alkoxy)carbonyl-C₁ -C₄ -alkyl, (C₁ -C₄ -alkyl-thio)carbonyl-C₁ -C₄-alkyl, aminocarbonyl-C₁ -C₄ -alkyl, (C₁ -C₄ -alkyl)aminocarbonyl-C₁ -C₄-alkyl, di(C₁ -C₄ -alkyl)amino-carbonyl-C₁ -C₄ -alkyl, C₃ -C₈-cycloalkyl, C₃ -C₈ -cycloalkyl-C₁ -C₄ -alkyl, phenyl, phenyl-C₁ -C₄-alkyl or 3- to 7-membered heterocyclyl or heterocyclyl-C₁ -C₄ -alkyl,wherein the heterocyclyl moieties consist of carbon ring members andfrom one to three heteroatoms as ring members, said heteroatoms beingselected from a group consisting of one to three nitrogen atoms, twooxygen atoms and two sulfur atoms, and wherein one carbon ring memberoptionally forms a carbonyl or a thiocarbonyl group, and wherein theheterocyclyl moieties are saturated, partially unsaturated oraromatic,wherein the cycloalkyl, the phenyl and the heterocyclyl ringsare unsubstituted or carry one to four substituents selected from thegroup consisting of halogen, cyano, nitro, amino, hydroxyl, carboxyl, C₁-C₄ -alkyl, C₁ -C₄ -haloalkyl, C₁ -C₄ -alkoxy, C₁ -C₄ -haloalkoxy, C₁-C₄ -alkylthio, C₁ -C₄ -haloalkylthio, C₁ -C₄ -alkylsulfonyl, C₁ -C₄-haloalkylsulfonyl, (C₁ -C₄ -alkyl)carbonyl, (C₁ -C₄-haloalkyl)carbonyl, (C₁ -C₄ -alkoxy)carbonyl, (C₁ -C₄-alkyl)carbonyloxy, (C₁ -C₄ -haloalkyl)carbonyloxy and di(C₁ -C₄-alkyl)amino, or R¹ and R² R⁷, or R² and R⁸ together form a1,2-ethanediyl, 1,3-propylene, tetramethylene, pentamethylene orethyleneoxyethylene chain which is unsubstituted or carries one to fourC₁ -C₄ -alkyl and/or one or two (C₁ -C₄ -alkoxy)carbonyl groups, or R¹and R² together are 1,2-phenylene which is unsubstituted or carries oneto three substituents selected from the group consisting of cyano,nitro, halogen, C₁ -C₄ -alkyl, C₁ -C₄ -haloalkyl, C₁ -C₄ -alkoxy and C₁-C₄ -haloalkoxy; R³ is cyano, halogen, alkyl, C₁ -C₄ -haloalkyl, C₁ -C₄-alkoxy or C₁ -C₄ -haloalkoxy; R⁴, R⁵ in each case are hydrogen orhalogen; R⁶ is halogen or C₁ -C₄ -haloalkyl; n is zero or one; or anagriculturally useful salt of a compound I.
 2. A herbicidal compositioncomprising a herbicidally effective amount of at least one2-phenylpyridine of the formula I or the agriculturally useful salt ofI, defined in claim 1, and at least one inert or solid carrier andoptionally at least one surfactant.
 3. A composition for the desiccationor defoliation of plants comprising an effective amount of at least one2-phenylpyridine of the formula I or the agriculturally useful salt ofI, defined in claim 1, and at least one inert liquid or solid carrierand optionally at least one surfactant.
 4. A method of controllingundesirable vegetation, which comprises treating plants, theirenvironment or seeds with an effective amount of at least one2-phenylpyridine of the formula I or the agriculturally useful salt ofI, defined in claim
 1. 5. A method for the desiccation or defoliation ofplants, which comprises treating the plants with an effective amount ofat least one 2-phenylpyridine of the formula I or the agriculturallyuseful salt of I, defined in claim
 1. 6. The method defined in claim 4,wherein the plant is cotton.
 7. The 2-phenylpyridine of the formula Idefined in claim 1, wherein X denotes CH₂, CH₂ --CH₂, CH₂ --CH(halogen),CH₂ --CH(CN), CH₂ --CH(CH₃), CH₂ --CH(COOCH₃), CH₂ --O--CH₂, CH═CH,CH═C(halogen), CH═C(CN), CH═C(CH₃), CH═C(COOCH₃) or O--CH₂.
 8. The2-phenylpyridine of the formula I defined in claim 1, wherein X denotesCH₂ --CH(halogen) or CH═C(halogen).
 9. The 2-phenylpyridine of theformula I defined in claim 1, wherein Y denotes oxygen.
 10. The2-phenylpyridine of the formula I defined in claim 1, wherein one of Z¹and Z² denotes oxygen.
 11. The 2-phenylpyridine of the formula I definedin claim 1, wherein Z¹ and Z² denote oxygen.
 12. The 2-phenylpyridine ofthe formula I defined in claim 1, wherein one of R¹ and R² or one of R⁷and R⁸ denotes hydrogen, C₁ -C₆ -alkyl, C₁ -C₆ -haloalkyl, C₃ -C₆-alkenyl, C₃ -C₆ -haloalkenyl, C₃ -C₆ -alkynyl, (C₁ -C₄-alkoxy)carbonyl-C₁ -C₄ -alkyl, C₃ -C₈ -cycloalkyl, C₃ -C₈-cycloalkyl-C₁ -C₄ -alkyl, phenyl, phenyl-C₁ -C₄ -alkyl, 3- to7-membered heterocyclyl or heterocyclyl-C₁ -C₄ -alkyl, or wherein R¹ andR² or R⁷, or R² and R⁸ together form a 1,2-ehtanediyl- or 1,3-propylenegroup.
 13. The 2-phenylpyridine of the formula I defined in claim 1,wherein one of R¹ and R² or one of R⁷ and R⁸ denotes hydrogen, C₁ -C₆-alkyl, C₃ -C₆ -alkenyl, C₃ -C₆ -alkynyl, C₃ -C₈ -cycloalkyl, phenyl orphenyl-C₁ -C₄ -alkyl, or wherein R¹ and R² together form a 1,3-propylenegroup.
 14. The 2-phenylpyridine of the formula I defined in claim 1,wherein R³ denotes cyano or chlorine.
 15. The 2-phenylpyridine of theformula I defined in claim 1, wherein R⁴ denotes hydrogen or fluorine.16. The 2-phenylpyridine of the formula I defined in claim 1, wherein R⁵denotes chlorine.
 17. The 2-phenylpyridine of the formula I defined inclaim 1, wherein R⁶ denotes trifluoromethyl.
 18. The 2-phenylpyridine ofthe formula I defined in claim 1, wherein n is zero.
 19. The2-phenylpyridine of the formula I defined in claim 1, wherein R³ denotescyano or chlorine and R⁴ denotes hydrogen or fluorine.
 20. The2-phenylpyridine of the formula I defined in claim 1, wherein R⁵ denoteschlorine and R⁶ denotes trifluoromethyl.